analitics

Pages

Wednesday, April 3, 2019

About Ninja IDE for python programming.

This I.D.E. is a very good tool for python programming and development.
The version of this tool is 2.3.
I tested with my Django project on Windows OS and works great.
The development team comes with this info:
NINJA-IDE (from the recursive acronym: "Ninja-IDE Is Not Just Another IDE"), is a cross-platform integrated development environment (IDE). NINJA-IDE runs on Linux/X11, Mac OS X and Windows desktop operating systems, and allows developers to create applications for several purposes using all the tools and utilities of NINJA-IDE, making the task of writing software easier and more enjoyable.
The official webpage can be found here.
If you want to use it with Django the easy way is to install the plugin for this area.
You can see all about the development team about page.

Saturday, March 30, 2019

Testing the python IMDbPY module with simple commands.

Today we tested a more innovative but useful method with python aaa mode.
The main reason I used this method is the lack of documentation.
Using this method, we have reached elements related to the use of reported methods and errors.
The test was done on a Fedora 29 Linux system with a classic install with the pip utility:
[mythcat@desk ~]$ pip install imdbpy --user
Collecting imdbpy
...
Successfully installed SQLAlchemy-1.3.1 imdbpy-6.6 
I used an example of a person's search in the IMDB database to test this method.
>>> from imdb import IMDb, IMDbError
>>> try:
...     im=IMDb()
...     people = im.search_person('Mel Gibson')
... except IMDbError as exc:
...     print(exc) 
Using the dir and print function will show the resulting output configuration and will have the following form:
>>> print(people)
[, , , , , , , , , , , , , , , , , , , ] 
I have used the dir function for a relative view of the options we have:
>>> print(dir(people))
['__add__', '__class__', '__contains__', '__delattr__', '__delitem__', '__delslice__', '__doc__', 
'__eq__', '__format__', '__ge__', '__getattribute__', '__getitem__', '__getslice__', 
'__gt__', '__hash__', '__iadd__', '__imul__', '__init__', '__iter__', '__le__', '__len__', 
'__lt__', '__mul__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__reversed__', 
'__rmul__', '__setattr__', '__setitem__', '__setslice__', '__sizeof__', '__str__', '__subclasshook__', 
'append', 'count', 'extend', 'index', 'insert', 'pop', 'remove', 'reverse', 'sort']
>>> print(dir(people[0]))
['_Container__role', '__bool__', '__class__', '__contains__', '__deepcopy__', '__delattr__', 
'__delitem__', '__dict__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', 
'__getitem__', '__gt__', '__hash__', '__init__', '__le__', '__len__', '__lt__', '__module__', 
'__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__setitem__', 
'__sizeof__', '__str__', '__subclasshook__', '__weakref__', '_additional_keys', '_clear', 
'_get_currentRole', '_get_roleID', '_getitem', '_image_key', '_init', '_reset', '_roleClass', 
'_roleIsPerson', '_set_currentRole', '_set_roleID', 'accessSystem', 'add_to_current_info', 
'append_item', 'asXML', 'billingPos', 'charactersRefs', 'clear', 'cmpFunct', 'copy', 'currentRole', 
'current_info', 'data', 'default_info', 'get', 'getAsXML', 'getID', 'get_charactersRefs', 
'get_current_info', 'get_fullsizeURL', 'get_namesRefs', 'get_titlesRefs', 'has_current_info', 
'has_key', 'infoset2keys', 'isSame', 'isSameName', 'isSamePerson', 'items', 'iteritems', 
'iterkeys', 'itervalues', 'key2infoset', 'keys', 'keys_alias', 'keys_tomodify', 'keys_tomodify_list', 
'modFunct', 'myID', 'myName', 'namesRefs', 'notes', 'personID', 'pop', 'popitem', 'reset', 'roleID', 
'set_current_info', 'set_data', 'set_item', 'set_mod_funct', 'set_name', 'setdefault', 'summary', 
'titlesRefs', 'update', 'update_charactersRefs', 'update_infoset_map', 'update_namesRefs', 
'update_titlesRefs', 'values']
Here are some simple examples of displaying using the print function to view content in output:

>>> print(people[0].values())
[u'Catalin', u'II', u'Catalin', u'Catalin (II)', u'Catalin (II)']
>>> print(people[0].data)
{u'name': u'Catalin', u'imdbIndex': u'II'}
>>> print(people[1].data.viewitems())
dict_items([(u'name', u'Moreno, Catalina Sandino')])
>>> print(people[1].data.values())
[u'Moreno, Catalina Sandino']
>>> print(people[0].getID())
2165704
>>> print(people[0].itervalues())
The built-in function iter takes an iterable object and returns an iterator.
>>> print(people[0].itervalues().next())
Catalin
>>> print(people[0].asXML()) 
The last line of code will return XML content.
This simple example simply illustrates how to access structured information through simple Python commands.

Saturday, March 23, 2019

Fix errors with the python errors encyclopedia.

Today I will present a website that I find very useful in learning and developing with the Python programming language.
This very short tutorial it is very useful for newcomers to get rid of all sorts of common questions about certain errors.
I encounter these types of errors when using stackoverflow account and can be a time consuming for most people who use it.
Try to read all about these errors on the python errors encyclopedia.

Wednesday, March 20, 2019

Using multiprocessing - a simple introduction.

The multiprocessing module was added to Python in version 2.6 and can be used with new python versions.
It was originally defined in PEP 371 by Jesse Noller and Richard Oudkerk.
The multiprocessing package also includes some APIs that are not in the threading module at all.
Python introduced the multiprocessing module to let us write parallel code.
You can use three basic classes: Process, Queue, and Lock, which will help you build a parallel program.
For more details, you can check the documentation of this python module.
Today, I will present in this tutorial two examples that highlight how to work with this python module.
The most basic approach is probably to use the Process class.
The Process class is very similar to the threading module’s Thread class.
It is also necessary to use the Manager because is responsible for coordinating shared information.
The source code is simple to understand and is commented on to see the intermediate steps.
Let's start with the first example that uses a function of adding two numbers in two processes.
import multiprocessing

def sum(a,b):
 t=a+b
 print ("sum is:",t)

if __name__ == '__main__':
 # create process processing_001 with target function and args of the target function
 processing_001 = multiprocessing.Process(target=sum, args=(7,6))
 processing_002 = multiprocessing.Process(target=sum, args=(1,1))
 # starting processing_001
 processing_001.start()
 # starting processing_002
 processing_002.start()
 #processes are started
 # stop processing_001 until is complete with join
 processing_001.join()
 # stop processing_002 until is complete with join
 processing_001.join()
 # result is C:\Python364>python.exe multiprocessing_001.py
 #sum is: 13
 #sum is: 2
The second example solves the next problem of the engineer who checks the speed of accomplishment of the tasks performed by two robots.
Three processes are created for each: robots and engineer.
All these processes are completed in the same dictionary resource using the Manager.
For each task performed by the robot (start/join processes), the robot finds a random execution rate (function random.random) that is then added to the result (result) with the robot name and execution speed.
Let's see the source code and the result:
import multiprocessing 
from multiprocessing import Process, Manager
import os
import random

def robot1(result):
 print("robot1 has ID process: {}".format(os.getpid()))
 speed_robot1=random.random()
 result["robot1"] = speed_robot1
 print ("worker speed tasks:",speed_robot1)
 #print (result)
 
def robot2(result):
 print("robot2 has ID process: {}".format(os.getpid()))
 speed_robot2=random.random()
 result["robot2"] = speed_robot2
 print ("worker speed tasks:",speed_robot2)
 #print (result)
 
def engineer(result):
 print("engineer has ID process: {}".format(os.getpid()))
 for key, value in result.items():
  print("Result: {}".format((key, value)))
 # you can add code to sort the values and print 
 # for key, value in sorted(result.items()):
 # print("Result: {}".format((key, value)))
 
if __name__ == '__main__':
 # show the main process
 print("the main ID process: {}". format(os.getpid()))
 # create a share dictionary resouce 
 manager = multiprocessing.Manager()
 result = manager.dict()
 # the process starts for  robot1
 ro1 = multiprocessing.Process(target=robot1, args=(result,))
 ro1.start()
 # the process starts for  robot2
 ro2 = multiprocessing.Process(target=robot2, args=(result,))
 ro2.start()
 # stops the robot1 process
 ro1.join()
 # stops the robot2 process
 ro2.join()
 # create the engineer process
 en = multiprocessing.Process(target=engineer, args=(result,))
 # start the process for the engineer
 en.start()
 # stops the engineer's process
 en.join()
The result is:
C:\Python364>python.exe multiprocessing_002.py
the main ID process: 7816
robot1 has ID process: 6476
worker speed tasks: 0.48279764083908094
robot2 has ID process: 7560
worker speed tasks: 0.44408591959008503
engineer has ID process: 7000
Result: ('robot1', 0.48279764083908094)
Result: ('robot2', 0.44408591959008503)

Sunday, March 17, 2019

Get bookmarks from your Firefox browser database.

This simple example tutorial is about reading the bookmarks from firefox database.
The database is an SQLite database.
You need to create a python file named: firefox_bookmarks.py.
Change your windows account on the bookmarks_path.
The script is simple to understand and comes with two functions: execute_query and get_bookmarks.
Follow the commented source code to understand how it's working the python script:
import os
import sqlite3

# execute a query on sqlite cursor
def execute_query(cursor, query):
    try:
        cursor.execute(query)
    except Exception as error:
        print(str(error) + "\n " + query)
# get bookmarks from firefox sqlite database file and print all
def get_bookmarks(cursor):
    bookmarks_query = """select url, moz_places.title, rev_host, frecency,
    last_visit_date from moz_places  join  \
    moz_bookmarks on moz_bookmarks.fk=moz_places.id where visit_count>0
    and moz_places.url  like 'http%'
    order by dateAdded desc;"""
    execute_query(cursor, bookmarks_query)
    for row in cursor:
        link = row[0]
        title = row[1]
        print(link,title)
# set the path of firefox folder with databases
bookmarks_path = "C:/Users/YOUR_WINDOWS_ACCOUNT/AppData/Roaming/Mozilla/Firefox/Profiles/"
# get firefox profile
profiles = [i for i in os.listdir(bookmarks_path) if i.endswith('.default')]
# get sqlite database of firefox bookmarks
sqlite_path = bookmarks_path+ profiles[0]+'/places.sqlite'
#
if os.path.exists(sqlite_path):
    firefox_connection = sqlite3.connect(sqlite_path)
cursor = firefox_connection.cursor()
get_bookmarks(cursor)
cursor.close()
The result of running the script comes with my bookmarks of Firefox:
C:\Python364>python.exe firefox_bookmarks.py
https://twitter.com/ Twitter. It's what's happening. 

Friday, March 15, 2019

Using Tornado - first steps...

About Tornado you can read at GitHub.
The basic info about this framework is this intro :
Tornado is a Python web framework and asynchronous networking library, originally developed at FriendFeed. By using non-blocking network I/O, Tornado can scale to tens of thousands of open connections, making it ideal for long polling, WebSockets, and other applications that require a long-lived connection to each user.
C:\Python364>git clone https://github.com/facebook/tornado.git
Cloning into 'tornado'...
remote: Enumerating objects: 51, done.
remote: Counting objects: 100% (51/51), done.
remote: Compressing objects: 100% (34/34), done.
remote: Total 22803 (delta 17), reused 51 (delta 17), pack-reused 22752
Receiving objects: 100% (22803/22803), 8.41 MiB | 2.18 MiB/s, done.
Resolving deltas: 100% (16735/16735), done.
Checking out files: 100% (302/302), done.

C:\Python364>cd tornado

C:\Python364\tornado>C:\Python364\python.exe setup.py install
running install
...
Processing dependencies for tornado==6.1.dev1
Finished processing dependencies for tornado==6.1.dev1
Use this demo chat to test it:
C:\Python364\tornado\demos\chat>C:\Python364\python.exe chatdemo.py
[I 190315 20:26:25 web:2162] 200 GET / (::1) 47.22ms
You can see the result into your browsers using http://localhost:8888
You can change port and address on this source code row with your IP address:
app.listen(options.port, '92.76.67.102')
The result is a chat example with Tornado framework.
The tornado comes with many demos for you, see all of this:
  • blog
  • chat
  • facebook
  • file_upload
  • helloworld
  • s3server
  • tcpecho
  • twitter
  • websocket
  • webspider

Friday, February 15, 2019

Install , test and fix error of the jupyter-book into python 3.

Jupyter Books lets you build an online book using a collection of Jupyter Notebooks and Markdown files. Its output is similar to the excellent Bookdown tool, and adds extra functionality for people running a Jupyter stack.
Read more about this on the official webpage.
Today I start to test this python module named jupyter-book.
I find some errors and I fixed to running well a demo jupyter-book instance.

C:\Python364\Scripts>pip install jupyter-book
Collecting jupyter-book
...
Installing collected packages: ruamel.yaml, jupyter-book
Successfully installed jupyter-book-0.4.1 ruamel.yaml-0.15.88
First I try to create a jupyter-book named catafest but I got this error:
C:\Python364>jupyter-book create catafest --demo
Traceback (most recent call last):
...
from nbclean import NotebookCleaner
ModuleNotFoundError: No module named 'nbclean'
The next step was to fix the error by install the nbclean python module and see all dependencies of python modules:
C:\Python364\Scripts>pip3.6.exe install nbclean
Collecting nbclean
...
Collecting nbgrader (from nbclean)
...
Collecting sqlalchemy (from nbgrader->nbclean)
...
Collecting alembic (from nbgrader->nbclean)
...
Collecting ipython<=6.2.1 (from nbgrader->nbclean)
...
Collecting jupyter-console<=5.2.0 (from nbgrader->nbclean)
...
Collecting Mako (from alembic->nbgrader->nbclean)
...
Collecting prompt-toolkit<2 .0.0="">=1.0.4 (from ipython<=6.2.1->nbgrader->nbclean)
...
Collecting prompt-toolkit<2 .0.0="">=1.0.4 (from ipython<=6.2.1->nbgrader->nbclean)
...
Building wheels for collected packages: nbgrader, sqlalchemy, alembic, Mako
...
Successfully built nbgrader sqlalchemy alembic Mako
Installing collected packages: sqlalchemy, Mako, python-editor, alembic, prompt-toolkit, ipython, 
jupyter-console, nbgrader, nbclean
...
Successfully installed Mako-1.0.7 alembic-1.0.7 ipython-6.2.1 jupyter-console-5.2.0 nbclean-0.3.2 
nbgrader-0.5.5 prompt-toolkit-1.0.15 python-editor-1.0.4 sqlalchemy-1.2.17 
Using again the jupyter-book to create catafest I got another error:
C:\Python364>jupyter-book create catafest--demo
Copying new book to: .\catafest
Copying over demo repository content
This is an error when I start to buid first time:
C:\Python364>jupyter-book build catafest
Convert and copy notebook/md files...
  0%|                                                                       | 0/35 [00:00
  File "c:\python364\lib\site-packages\jupyter_book\main.py", line 31, in main
    commands[args.command]()
  File "c:\python364\lib\site-packages\jupyter_book\build.py", line 266, in build_book
    lines = ff.readlines()
  File "c:\python364\lib\encodings\cp1252.py", line 23, in decode
    return codecs.charmap_decode(input,self.errors,decoding_table)[0]
UnicodeDecodeError: 'charmap' codec can't decode byte 0x9d in position 183: character maps to  
The reason is the python 3.x and can be fixed by change the encoding into this file:
c:\python364\lib\site-packages\jupyter_book\build.py with this:
with open(path_new_file, 'r',encoding='utf-8') as ff:
The next step is to build the catafest jupyter-book:
C:\Python364>jupyter-book build catafest
Convert and copy notebook/md files...
... 
My GitHub account is catafest and I used this link to create a new repo named catafest_jupyter-book:
https://github.com/new
You need to use root folder use this commands:
C:\Python364\catafest>cd ..

C:\Python364>git clone https://github.com/catafest/catafest_jupyter-book
Cloning into 'catafest_jupyter-book'...
warning: You appear to have cloned an empty repository.
Copy all files and folders from catafest folder to catafest_jupyter-book folder and use GITHUB commands to upload to the web:
C:\Python364>cd catafest_jupyter-book

C:\Python364\catafest_jupyter-book>git add ./*

C:\Python364\catafest_jupyter-book>git commit -m "adding my first jupyter book!"

C:\Python364\catafest_jupyter-book>git push
Username for 'https://github.com': catafest
Password for 'https://catafest@github.com':
Enumerating objects: 347, done.
Counting objects: 100% (347/347), done.
Delta compression using up to 2 threads.
Compressing objects: 100% (304/304), done.
Writing objects: 100% (347/347), 1.40 MiB | 541.00 KiB/s, done.
Total 347 (delta 74), reused 0 (delta 0)
remote: Resolving deltas: 100% (74/74), done.
To https://github.com/catafest/catafest_jupyter-book
 * [new branch]      master -> master
You can make GITHUB settings with a new gh-pages branch to see into your browser.

Thursday, February 14, 2019

Using python with documents files.

Today I tested with python version 3.6.4 two python modules: python-docx and openpyxl.
This python modules let us to deal with document files like: docx, xlsx, xlsm, xltx, xltm.
First python module named python-docx is a Python library for creating and updating Microsoft Word (.docx) files.
The documentation of this python module can be found here.
Let's start with a simple example.
C:\Python364>cd Scripts
C:\Python364\Scripts>pip3.6.exe install python-docx
Collecting python-docx
...
Successfully installed python-docx-0.8.10
Let's start with the import step:
C:\Python364>python.exe
Python 3.6.4 (v3.6.4:d48eceb, Dec 19 2017, 06:54:40) [MSC v.1900 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import docx
>>> dir(docx)
['Document', 'ImagePart', 'RT', '__builtins__', '__cached__', '__doc__', '__file__', '__loader__', '
__name__', '__package__', '__path__', '__spec__', '__version__', 'api', 'blkcntnr', 'compat', 'dml',
 'document', 'enum', 'exceptions', 'image', 'opc', 'oxml', 'package', 'parts', 'section', 'settings'
, 'shape', 'shared', 'styles', 'text']
Let's create a document with this python module and add some text and an image:
C:\Python364>python.exe
Python 3.6.4 (v3.6.4:d48eceb, Dec 19 2017, 06:54:40) [MSC v.1900 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import docx
>>> mydoc = docx.Document()
>>> mydoc.add_paragraph('This is a text')
>>> mydoc.add_picture('icon.png',width=docx.shared.Inches(1),height=docx.shared.Inches(1))
>>> mydoc.save('test.docx')
Another python module is openpyxl.
This python module let you to read/write Excel 2010 xlsx/xlsm/xltx/xltm files.
C:\Python364\Scripts>pip3.6.exe install openpyxl
Collecting openpyxl
...
Successfully installed et-xmlfile-1.0.1 jdcal-1.4 openpyxl-2.6.0
Let's test it:
C:\Python364>python.exe
Python 3.6.4 (v3.6.4:d48eceb, Dec 19 2017, 06:54:40) [MSC v.1900 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> from openpyxl import load_workbook
>>> w = load_workbook(filename='test.xlsx',read_only=True)
>>> print(w.sheetnames)
['Sheet1', 'TestSheet2']
>>> s=w['Sheet1']
>>> for row in s.rows:
...     for c in row:
...             print(c.value)
...
A1
None
ABC
None
None
NOP

Sunday, February 10, 2019

Using the asciimatics and pyfiglet python modules

This is a simple example how to use the asciimatics and pyfiglet python modules with python version 3.6.4.
First you need to install with the pip tool.
The source code is simple and start with the import it.
The Fire, Print and Screen is used to show the fire effect and print text with Figlet and FigletText.
Because the fire and text use the console application I used the default Screen Buffer Size set to 80.
The Screen.wrapper(my_work_web) show all effects from the my_work_web.
In this area is created variables for font type: banner_font and web_font.
The main reason I named the web_font was to show my web page but the size of the over the screensize.
I tested most of the fonts from pyfiglet python module but I cannot find one to show a web page link.
This is the source code I tested:
# -*- coding: utf-8 -*-
"""
@author: catafest
"""

from asciimatics.renderers import FigletText, Fire
from asciimatics.scene import Scene
from asciimatics.screen import Screen
from asciimatics.effects import Print
from asciimatics.exceptions import ResizeScreenError
from pyfiglet import Figlet
import sys

def my_work_web(screen):
    banner_font = "banner3"
    web_font = "block"
    scenes = []
    effects = [
        Print(screen,
              Fire(screen.height, 80, "*" * 70, 0.8, 60, screen.colours,
                   bg=screen.colours >= 256),
              0,
              speed=1,
              transparent=False),
        Print(screen,
              FigletText("Follow ", banner_font),
              (screen.height - 4) // 2,
              colour=Screen.COLOUR_BLUE,
              speed=1,
              stop_frame=30),
        Print(screen,
              FigletText("me", banner_font),
              (screen.height - 4) // 2,
              colour=Screen.COLOUR_BLUE,
              speed=1,
              start_frame=30,
              stop_frame=50),
        Print(screen,
              FigletText("on web", banner_font),
              (screen.height - 4) // 2,
              colour=Screen.COLOUR_BLUE,
              speed=1,
              start_frame=50,
              stop_frame=70),
        Print(screen,
              FigletText("catafest", banner_font),
              (screen.height - 4) // 2,
              colour=Screen.COLOUR_BLUE,
              speed=1,
              start_frame=70),
    ]
    scenes.append(Scene(effects, 100))

    text = Figlet(font=web_font, width=300).renderText("bye!")
    width = max([len(x) for x in text.split("\n")])

    effects = [
        Print(screen,
              Fire(screen.height, 80, "*" * 70, 0.8, 60, screen.colours),
              0,
              speed=1,
              transparent=False),

        Print(screen,
              FigletText("bye!", web_font),
              (screen.height - 2)  // 2,
              colour=Screen.COLOUR_WHITE,
              bg=Screen.COLOUR_BLUE,
              speed=1)
    ]
    scenes.append(Scene(effects, -1))
    screen.play(scenes, stop_on_resize=True)


if __name__ == "__main__":
    while True:
        try:
            Screen.wrapper(my_work_web)
            sys.exit(0)
        except ResizeScreenError:
            pass
The result of this source code is this:

Monday, January 28, 2019

Testing imageio python module.

This python module comes with this intro from pypi website:
Imageio is a Python library that provides an easy interface to read and write a wide range of image data, including animated images, volumetric data, and scientific formats. It is cross-platform, runs on Python 2.7 and 3.4+, and is easy to install.
Let's install this python module:
C:\>cd C:\Python364
C:\Python364>cd Scripts
C:\Python364\Scripts>pip3.6.exe install imageio
Collecting imageio
...
Successfully built imageio
Installing collected packages: imageio
Successfully installed imageio-2.4.1
You are using pip version 18.0, however version 18.1 is available.
You should consider upgrading via the 'python -m pip install --upgrade pip' comm
and.
I tested with a simple read medical data (DICOM - CT-MONO2-16-brain), see here.
The Digital Imaging and Communications in Medicine (DICOM) standard start with the basic idea is that patient and machine-readable information is embedded within a file (usually an image) as it’s created or converted.
This is a simple example without security.
Without encrypted connections between applications, anyone on the network could intercept the DICOM files and extract the patient information.
The Imageio provides a range of example images:
  1. Read an image;
  2. Iterate over frames in a movie;
  3. Grab screenshot or image from the clipboard;
  4. Convert a movie;
  5. Writing videos with FFMPEG and vaapi;
All file formats (93 files type ) can be read by this python module, see webpage here.
The examples from the official webpage work well.
Only the example with the DICOM file cannot be tested.
The main reason: I try to find a DICOM file but I don't find one.

Saturday, January 26, 2019

Testing the webpy python module.

Today I wrote about another python module named web.py.
The reasons I start this tutorial come from google page of SDK for App Engine.
The Google come with these options of the following frameworks can be used with Python programming language:
  • Flask;
  • Django;
  • Pyramid;
  • Bottle;
  • web.py
  • Tornado
I started in the past to learn and use Django and I tested with Flask and Bottle and today is web.py python module.
First, about this python module I can tell you is a simple web framework and comes with a web.py slogan:
Think about the ideal way to write a web app. Write the code to make it happen.
C:\Python364\Scripts>pip install web.py==0.40-dev1
Collecting web.py==0.40-dev1
  Downloading https://files.pythonhosted.org/packages/db/a5/8dfacc190908f9876632
69a92efa682175c377e3f7eab84ed0a89c963b47/web.py-0.40.dev1.tar.gz (117kB)
    100% |████████████████████████████████| 122kB 936kB/s
Building wheels for collected packages: web.py
  Building wheel for web.py (setup.py) ... done
  Stored in directory: C:\Users\catafest\AppData\Local\pip\Cache\wheels\1b\15\12
\4fd91f5ed7e3c8aae085050cce83f72b7ca4f463bf3e67d2b7
Successfully built web.py
Installing collected packages: web.py
Successfully installed web.py-0.40.dev1
Let's test the example from the official website:
C:\Python364>python.exe
Python 3.6.4 (v3.6.4:d48eceb, Dec 19 2017, 06:54:40) [MSC v.1900 64 bit (AMD64)]
 on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import web
>>>
... urls = (
...     '/(.*)', 'hello'
... )
>>> app = web.application(urls, globals())
>>>
>>> class hello:
...     def GET(self, name):
...         if not name:
...             name = 'World'
...         return 'Hello, ' + name + '!'
...
>>> if __name__ == "__main__":
...     app.run()
...
http://0.0.0.0:8080/
127.0.0.1:50542 - - [27/Jan/2019 07:30:28] "HTTP/1.1 GET /" - 200 OK
127.0.0.1:50542 - - [27/Jan/2019 07:30:28] "HTTP/1.1 GET /favicon.ico" - 200 OK
The server starts at 0.0.0.0 (invalid address) and can see the result at 127.0.0.1:8080.

Tuesday, January 1, 2019

Detect nudity with nudepy python module.

Today I tested another python module named nudepy.
You can find it here.
This python module is a port of nude.js to Python.
Let's start the tutorial with the installation:
C:\Python364\Scripts>cd ..

C:\Python364>cd Scripts

C:\Python364\Scripts>pip install nudepy
Requirement already satisfied: nudepy in c:\python364\lib\site-packages (0.4)
Requirement already satisfied: pillow in c:\python364\lib\site-packages (from nu
depy) (5.3.0)
To test this python module, I used four images with the idea of a nude image
This image is the result of all images of the test.

This image files are named:
  • test_nude_001.jpg
  • test_nude_002.jpg
  • test_nude_003.jpg
  • test_nude_004.jpg
Let's see the script:
# for select jpeg files
import os, fnmatch
# import nude python module
import nude
from nude import Nude
#
nude_jpegs=fnmatch.filter(os.listdir('.'), '*nude*.jpg')
print(nude_jpegs)
for found_file in nude_jpegs:
    print (found_file)
    print("Nude file: ",nude.is_nude(str(found_file)))
    n = Nude(str(found_file))
    n.parse()
    print("and test result: ", n.result, n.inspect())
    print("====================")
The result of the output script is this:
C:\Python364>python.exe test_nude.py
['test_nude_001.jpg', 'test_nude_002.jpg', 'test_nude_003.jpg', 'test_nude_004.j
pg']
test_nude_001.jpg
Nude file:  False
and test result:  False #
====================
test_nude_002.jpg
Nude file:  False
and test result:  False #
====================
test_nude_003.jpg
Nude file:  False
and test result:  False #
====================
test_nude_004.jpg
Nude file:  True
and test result:  True #
====================

Thursday, December 27, 2018

Using LibROSA python module.

This python module named LibROSA is a python package for music and audio analysis and provides the building blocks necessary to create music information retrieval systems.
C:\Python364>cd Scripts
C:\Python364\Scripts>pip install librosa
Collecting librosa
...
Successfully installed audioread-2.1.6 joblib-0.13.0 librosa-0.6.2 llvmlite-0.26.0 numba-0.41.0 resampy-0.2.1 
scikit-learn-0.20.2
Let's create one waveform and a spectrogram with this python module.
The waveform (for sound) the term describes a depiction of the pattern of sound pressure variation (or amplitude) in the time domain.
A spectrogram (known also like sonographs, voiceprints, or voicegrams) is a visual representation of the spectrum of frequencies of sound or other signals as they vary with time.
I used a free WAV file sound from here.
The result of the waveform and spectrogram for that audio file is shown into next screenshots:


My example show first the waveform and you need to close the it to see the spectrogram.
Let's see the source code of this example:
import librosa
import librosa.display
import matplotlib.pyplot as plt
plt.figure(figsize=(14, 5))
path = "merry_christmas.wav"
out,samples = librosa.load(path)
print(out.shape, samples)
librosa.display.waveplot(out, sr=samples)
plt.show()
stft_array = librosa.stft(out)
stft_array_db = librosa.amplitude_to_db(abs(stft_array))
librosa.display.specshow(stft_array_db,sr=samples,x_axis='time', y_axis='hz')
plt.colorbar()
plt.show()

Tuesday, December 25, 2018

Using python modules: mayavi and moviepy - part 001.

This is a simple example with two modules named: mayavi and moviepy.
Let's see the introduction of these python modules:
Mayavi2 is a general purpose, cross-platform tool for 3-D scientific data visualization. Its features include:

  • Visualization of scalar, vector and tensor data in 2 and 3 dimensions.
  • Easy scriptability using Python.
  • Easy extendibility via custom sources, modules, and data filters.
  • Reading several file formats: VTK (legacy and XML), PLOT3D, etc.
  • Saving of visualizations.
  • Saving rendered visualization in a variety of image formats.
  • Convenient functionality for rapid scientific plotting via mlab
MoviePy is a Python module for video editing, which can be used for basic operations (like cuts, concatenations, title insertions), video compositing (a.k.a. non-linear editing), video processing, or to create advanced effects. It can read and write the most common video formats, including GIF.
The installation with pip3.6 tool:
C:\Python364\Scripts>pip3.6.exe install mayavi
Requirement already satisfied: mayavi in c:\python364\lib\site-packages (4.6.2)
...
C:\Python364\Scripts>pip3.6.exe install moviepy
Collecting moviepy
...
Installing collected packages: tqdm, moviepy
Successfully installed moviepy-0.2.3.5 tqdm-4.28.1
Let's create a simple example with these python modules.
First example:
C:\Python364>python.exe
Python 3.6.4 (v3.6.4:d48eceb, Dec 19 2017, 06:54:40) [MSC v.1900 64 bit (AMD64)]
 on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import mayavi.mlab as mlab
>>> f = mlab.gcf()
>>> f.scene._lift()
>>>
I choose the most common filter math function: the sinc function, known as sine cardinal:
In signal processing, a sinc filter is an idealized filter that removes all frequency components above a given cutoff frequency, without affecting lower frequencies, and has linear phase response. The filter's impulse response is a sinc function in the time domain, and its frequency response is a rectangular function.
I create the example to show you a sinc function by time.
This is my output (is not the result of the frequency response of the Fourier transform of the rectangular function).

Let's see the source code:
# import python modules
import numpy as np
import mayavi.mlab as mlab
import moviepy.editor as mpy
# duration of the animation in seconds 
duration= 2
# create the grid of points for x and y
x, y = np.mgrid[-30:30:100j, -30:30:100j]
# create the size figure
fig = mlab.figure(size=(640,480), bgcolor=(1,1,1))
# create the plane surface
r = np.sqrt(x**2 + y**2)
# this fix issue https://github.com/enthought/mayavi/issues/702
fig = mlab.gcf()
fig.scene._lift()
# create all frames 
def make_frame(t):
    # clear the area 
    mlab.clf()
    #blend surface by z over time t step is 0.05
    z = np.sin(r*t)/r
    # create surface 
    mlab.surf(z, warp_scale='auto')
    return mlab.screenshot(antialiased=True)
# create animation movie clip
animation = mpy.VideoClip(make_frame,duration=duration)
# write file like a GIF 
animation.write_gif("sinc.gif", fps=20)

Monday, December 24, 2018

Python Qt5 : the most simple QTreeWidget - part 001.

The QTreeWidget is more complex in order to accomplish a simple development issue.
Today, I will show you how is the first step to start it.
This simple example will follow these goals:
  • create a simple QTreeWidget;
  • use the most simple way to do that;
  • do not use the class object;
  • show files and folders;
The example do not have any feature for and show my C drive:
  • filter, sort and drag and drop;
The result of this example:

Saturday, December 22, 2018

Using pytorch - the final of story.

Let's continue our story with the child and the gift.
The child saw the gift and his first thought was the desire to know.
The basic forming unit of a neural network is a perceptron.
He saw that he was not too big and his eyes lit up.
To compute the output will multiply input with respective weights and compare with a threshold value.
Each perceptron also has a bias which can be thought of as how much flexible the perceptron is.
This process is of evolving a perceptron to what a now called an artificial neuron.
The next step is the artificial network and is all artificial neuron and edges between.
He touched him in the corners and put his hand on his surface.
The activation function is mostly used to make a non-linear transformation which allows us to fit nonlinear hypotheses or to estimate the complex functions.
He began to understand that he had a special and complex form.
This artificial network is built from start to end from:
  • Input Layer an X as an input matrix;
  • Hidden Layers a matrix dot product of input and weights assigned to edges between the input and hidden layer, then add biases of the hidden layer neurons to respective inputs and use this to update all weights at the output and hidden layer to use update biases at the output and hidden layer.
  • Output Layer an y as an output matrix;
Without too much thoughts he began to break out of the gift in the order in which he touched it.
This weight and bias of the updating process are known as back propagation.
To computed the output and this process is known as forward propagation.
Several moves were enough to complete the opening of the gift.
He looked and understood that the size of the gift is smaller, but the gift was thankful to him.
This forward and back propagation iteration is known as one training iteration named epoch.
The next example I created from an old example I saw on the internet and is the most simple way to show you the steps from this last part of the story:
##use an neural network in pytorch
import torch

#an input array
X = torch.Tensor([[1,0,1],[0,1,1],[0,1,0]])

#the output
y = torch.Tensor([[1],[1],[0]])

#the Sigmoid Function
def sigmoid (x):
  return 1/(1 + torch.exp(-x))

#the derivative of Sigmoid Function
def derivatives_sigmoid(x):
  return x * (1 - x)

#set the variable initialization
epoch=1000 #training iterations is epoch
lr=0.1 #learning rate value
inputlayer_neurons = X.shape[1] #number of features in data set
hiddenlayer_neurons = 3 #number of hidden layers neurons
output_neurons = 1 #number of neurons at output layer

#weight and bias initialization
wh=torch.randn(inputlayer_neurons, hiddenlayer_neurons).type(torch.FloatTensor)
print("weigt = ", wh)
bh=torch.randn(1, hiddenlayer_neurons).type(torch.FloatTensor)
print("bias = ", bh)
wout=torch.randn(hiddenlayer_neurons, output_neurons)
print("wout = ", wout)
bout=torch.randn(1, output_neurons)
print("bout = ", bout)

for i in range(epoch):

  #Forward Propogation
  hidden_layer_input1 = torch.mm(X, wh)
  hidden_layer_input = hidden_layer_input1 + bh
  hidden_layer_activations = sigmoid(hidden_layer_input)
 
  output_layer_input1 = torch.mm(hidden_layer_activations, wout)
  output_layer_input = output_layer_input1 + bout
  output = sigmoid(output_layer_input1)

  #Backpropagation
  E = y-output
  slope_output_layer = derivatives_sigmoid(output)
  slope_hidden_layer = derivatives_sigmoid(hidden_layer_activations)
  d_output = E * slope_output_layer
  Error_at_hidden_layer = torch.mm(d_output, wout.t())
  d_hiddenlayer = Error_at_hidden_layer * slope_hidden_layer
  wout += torch.mm(hidden_layer_activations.t(), d_output) *lr
  bout += d_output.sum() *lr
  wh += torch.mm(X.t(), d_hiddenlayer) *lr
  bh += d_output.sum() *lr
 
print('actual :\n', y, '\n')
print('predicted :\n', output)
The result is for 100 and 1000 epoch value and show us how close is the actual input (1,1,0) to the predicted results.
See also the weight and bias initialization of the artificial network is created random by torch.randn.
If I added this in my story it would sound like this:
The child's thoughts began to flinch in wanting to finish faster and find the gift.
C:\Python364>python.exe pytorch_test_002.py
weigt =  tensor([[-0.9364,  0.4214,  0.2473],
        [-1.0382,  2.0838, -1.2670],
        [ 1.2821, -0.7776, -1.8969]])
bias =  tensor([[-0.3604, -0.8943,  0.3786]])
wout =  tensor([[-0.5408],
        [ 1.3174],
        [-0.7556]])
bout =  tensor([[-0.4228]])
actual :
 tensor([[1.],
        [1.],
        [0.]])

predicted :
 tensor([[0.5903],
        [0.6910],
        [0.6168]])

C:\Python364>python.exe pytorch_test_002.py
weigt =  tensor([[ 1.2993,  1.5142, -1.6325],
        [ 0.0621, -0.5370,  0.1480],
        [ 1.5673, -0.2273, -0.3698]])
bias =  tensor([[-2.0730, -1.2494,  0.2484]])
wout =  tensor([[ 0.6642],
        [ 1.6692],
        [-0.4087]])
bout =  tensor([[0.3340]])
actual :
 tensor([[1.],
        [1.],
        [0.]])

predicted :
 tensor([[0.9417],
        [0.8510],
        [0.2364]])

Friday, December 21, 2018

Python Qt5 : simple draw with QPainter.

Using the QPainter is more complex than a simple example.
I try to create a simple example in order to have a good look at how can be used.
The main goal was to understand how can have the basic elements of QPainter.
The result of my example is this:

Here is my example with all commented lines for a good approach:
import sys 
from PyQt5 import QtGui, QtWidgets 
from PyQt5.QtGui import QPainter, QBrush, QColor
from PyQt5.QtCore import Qt, QPoint 
class My_QPainter(QtWidgets.QWidget): 
    def paintEvent(self, event): 
        # create custom QPainter
        my_painter = QtGui.QPainter() 
        # start and set my_painter
        my_painter.begin(self) 
        my_painter.setRenderHint(my_painter.TextAntialiasing, True)
        my_painter.setRenderHint(my_painter.Antialiasing, True)
        #set color for pen by RGB
        my_painter.setPen(QtGui.QColor(0,0,255)) 
        # draw a text on fixed coordinates
        my_painter.drawText(220,100, "Text at 220, 100 fixed coordinates") 
        # draw a text in the centre of my_painter   
        my_painter.drawText(event.rect(), Qt.AlignCenter, "Text centerd in the drawing area") 
        #set color for pen by Qt color  
        my_painter.setPen(QtGui.QPen(Qt.green, 1)) 
        # draw a ellipse
        my_painter.drawEllipse(QPoint(100,100),60,60) 
        # set color for pen by property
        my_painter.setPen(QtGui.QPen(Qt.blue, 3, join = Qt.MiterJoin)) 
        # draw a rectangle
        my_painter.drawRect(80,160,100,100) 
        # set color for pen by Qt color 
        my_painter.setPen(QtGui.QPen(Qt.red, 2))
        # set brush 
        my_brush = QBrush(QColor(33, 33, 100, 255), Qt.DiagCrossPattern)
        my_painter.setBrush(my_brush)
        # draw a rectangle and fill with the brush 
        my_painter.drawRect(300, 300,180, 180)
        my_painter.end() 
# create application  
app = QtWidgets.QApplication(sys.argv) 
# create the window application from class
window = My_QPainter() 
# show the window
window.show() 
# default exit 
sys.exit(app.exec_())

Thursday, December 20, 2018

Python 3.6.4 : Learning OpenCV - centroids.

Today I was a little lazy.
I studied a little on the internet.
The last aspect was related to centroids.
An example I studied before TV news was from this webpage.
About centroid you can read here.
The result of the source code from a video with Simona Halep.

Tuesday, December 18, 2018

Python Qt5 : complex QML file.

Today, I will show you how to have a more complex custom application with PyQt5 and QML file.
You need to create into your python folder a new folder named QMLCustom.
Into this file create two python files named: __init__.py and QMLCustom.py.
The __init__ will be an empty file.
Into your python folder installation (where you create the QMLCustom folder), create a new QML_custom.qml file.
The QML_custom.qml file will have this:
import QtQuick 2.0
import SDK 1.0
import QtQuick.Layouts 1.1

Rectangle {
    id: appwnd
    visible: true
    width: 640
    height: 480

    property int columns : 2
    property int rows : 2

    Rectangle {
        anchors.fill: parent
        color: "#00f"
    }

    GridView {
        id: grid
        anchors.fill: parent
        cellWidth: Math.max(width/2, height/2);
        cellHeight: Math.max(width/2, height/2)
        model: dashModel
        delegate : Rectangle {
            Layout.alignment: Layout.Center
            width: grid.cellWidth
            height: grid.cellHeight
            color: "#0ff"
            border.color: "#fff"
            border.width: 10

            Text {
                id: name
                anchors.horizontalCenter: parent.horizontalCenter
                anchors.bottom: parent.bottom
                anchors.leftMargin:15
                anchors.topMargin: 15
                width: parent.width 
                height: parent.height
                textFont {
                    family: "Halvetica"
                    italic: false
                    pointSize:20
                }
                suffixText: suffix
            }

        }
        onWidthChanged: {
            grid.cellWidth = grid.width/appwnd.columns;
        }

        onHeightChanged: {
            grid.cellHeight = grid.height/appwnd.rows
        }
    }

    ListModel {
        id: dashModel
        ListElement {
            tagName: "Text"
            suffix: "First text"
        }
        ListElement {
            tagName: "Text"
            suffix: "Next text"
        }         
    }
} 
If you read this you will see the qml type file has two imports and a text.
The imports are used to load it and the text file is used to describe what we need.
In this case is created a Rectangle, GridView and one ListModel with two ListElement.
All of this part will be a link to the QMLCustom.py file.
For example: follow the suffixText from qml file suffixText: suffix into QMLCustom.py file (decorator def suffixText(self, text)).
Into the QMLCustom folder you need to fill the QMLCustom.py with this:
import PyQt5
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
from PyQt5.QtCore import pyqtProperty, pyqtSignal, pyqtSlot
from PyQt5.QtQuick import QQuickPaintedItem, QQuickItem
from PyQt5.QtGui import QPainter
from PyQt5 import QtCore

class QMLCustom(QQuickPaintedItem):
    #
    class DialType():
        FullDial = 0
        MinToMax = 1
        NoDial = 2
    #
    sizeChanged = pyqtSignal()
    valueChanged = pyqtSignal()
    #
    backgroundColorChanged = pyqtSignal()
    #
    textColorChanged = pyqtSignal()
    suffixTextChanged = pyqtSignal()
    showTextChanged = pyqtSignal()
    textFontChanged = pyqtSignal()

    def __init__(self, parent=None):
        super(QMLCustom, self).__init__(parent)

        self.setWidth(100)
        self.setHeight(100)
        self.setSmooth(True)
        self.setAntialiasing(True)

        self._Size = 100
        self._DialWidth = 15
        self._SuffixText = ""
        self._BackgroundColor = Qt.transparent
        self._TextColor = QColor(0, 0, 0)
        self._ShowText = True
        self._TextFont = QFont()

    def paint(self, painter):
        painter.save()

        size = min(self.width(), self.height())       
        self.setWidth(size)
        self.setHeight(size)
        rect = QRectF(0, 0, self.width(), self.height()) 
        painter.setRenderHint(QPainter.Antialiasing)
        
        painter.restore()

        painter.save()
        painter.setFont(self._TextFont)
        offset = self._DialWidth / 2
        if self._ShowText:
            painter.drawText(rect.adjusted(offset, offset, -offset, -offset), Qt.AlignCenter, self._SuffixText)
        else:
            painter.drawText(rect.adjusted(offset, offset, -offset, -offset), Qt.AlignCenter, self._SuffixText)
        painter.restore()

    @QtCore.pyqtProperty(str, notify=sizeChanged)
    def size(self):
        return self._Size

    @size.setter
    def size(self, size):
        if self._Size == size:
            return
        self._Size = size
        self.sizeChanged.emit()

    @QtCore.pyqtProperty(float, notify=valueChanged)
    def value(self):
        return self._Value

    @value.setter
    def value(self, value):
        if self._Value == value:
            return
        self._Value = value
        self.valueChanged.emit()


    @QtCore.pyqtProperty(QColor, notify=backgroundColorChanged)
    def backgroundColor(self):
        return self._BackgroundColor

    @backgroundColor.setter
    def backgroundColor(self, color):
        if self._BackgroundColor == color:
            return
        self._BackgroundColor = color
        self.backgroundColorChanged.emit()


    @QtCore.pyqtProperty(QColor, notify=textColorChanged)
    def textColor(self):
        return self._TextColor

    @textColor.setter
    def textColor(self, color):
        if self._TextColor == color:
            return
        self._TextColor = color
        self.textColorChanged.emit()  

    @QtCore.pyqtProperty(str, notify=suffixTextChanged)
    def suffixText(self):
        return self._SuffixText

    @suffixText.setter
    def suffixText(self, text):
        if self._SuffixText == text:
            return
        self._SuffixText = text
        self.suffixTextChanged.emit()

    @QtCore.pyqtProperty(str, notify=showTextChanged)
    def showText(self):
        return self._ShowText

    @showText.setter
    def showText(self, show):
        if self._ShowText == show:
            return
        self._ShowText = show


    @QtCore.pyqtProperty(QFont, notify=textFontChanged)
    def textFont(self):
        return self._TextFont

    @textFont.setter
    def textFont(self, font):
        if self._TextFont == font:
            return
        self._TextFont = font
        self.textFontChanged.emit()
This is a base python module that allows you to use the qml file and show it into your application.
The QMLCustom.py use a class (with pyqtSignal and paint to link all data with decorators) to be used into your application.
This can be a little difficult to follow but if you deal with a tool like QtCreator editor you will understand how this integrated GUI layout and forms designer with this script.
The last part is more simple and is the application.
This script uses both the custom python module QMLCustom and the qml file.
Create a python file into your folder python installation fill with the next script and run it:
import sys
import os
import subprocess

from QMLCustom.QMLCustom import QMLCustom

from PyQt5.QtCore import QUrl, Qt, QObject, pyqtSignal, pyqtSlot
from PyQt5.QtGui import QGuiApplication, QCursor
from PyQt5.QtQuick import QQuickView
from PyQt5.QtQml import qmlRegisterType
from OpenGL import GLU

class App(QGuiApplication):
 def __init__(self, argv):
  super(App, self).__init__(argv)

if __name__ == '__main__':
 try:
  app = App(sys.argv)
  
  qmlRegisterType(QMLCustom, "SDK", 1,0, "Text")

  view = QQuickView()
  ctxt = view.rootContext()
  view.setSource(QUrl("QML_custom.qml"))
  view.show()
  ret = app.exec_()

 except Exception as e:
  print (e)
The result is this:

Python Qt5 : application with QML file.

The PyQt5 includes QML as a means of declaratively describing a user interface and is possible to write complete standalone QML applications.
Using QML file is different from the versions PyQt5 and old PyQt4.
Using this type of application can let you solve custom and style application.
I create a simple example but can create your python module with a class with new type of style.
This can be used with qmlRegisterType for your new python class type.
Let's see the example:
The main python file:
from PyQt5.QtNetwork import *
from PyQt5.QtQml import *
from PyQt5.QtWidgets import *
from PyQt5.QtCore import *

class MainWin(object):
    def __init__(self):
        self.eng = QQmlApplicationEngine()
        self.eng.load('win.qml')
        win = self.eng.rootObjects()[0]   
        win.show()

if __name__ == '__main__':
    import sys
    App = QApplication(sys.argv)
    Win = MainWin()
    sys.exit(App.exec_())
The QML file:
import QtQuick 2.2
import QtQuick.Controls 1.0
ApplicationWindow {
    id: main
    width: 640
    height: 480
    color: 'blue'
 }
The result is a blue window.

Monday, December 17, 2018

Using pytorch - another way.

Yes. I used pytorch and is working well. Is not perfect the GitHub come every day with a full stack of issues.
Let's continue this series with another step: torchvision.
If you take a closer look at that gift, you will see that it comes with a special label that can really help us.
This label is a named torchvision.
The torchvision python module is a package consists of popular datasets, model architectures, and common image transformations for computer vision.
Most operations pass through filters and date already recognized.
  • torchvision.datasets: (MNIST,Fashion-MNIST,EMNIST,COCO,LSUN,ImageFolder,DatasetFolder,Imagenet-12,CIFAR,STL10,SVHN,PhotoTour,SBU,Flickr,VOC)
  • torchvision.models: (Alexnet,VGG,ResNet,SqueezeNet,DenseNet,Inception v3)
  • torchvision.transforms: (Transforms on PIL Image,Transforms on torch.*Tensor,Conversion Transforms,Generic Transforms,Functional Transforms)
  • torchvision.utils
This part of the gift help you to load and prepare dataset but into certain order.
Using this special label, we will be able to use the gift-breaking information.
Let's see the example:
C:\Python364>python.exe
Python 3.6.4 (v3.6.4:d48eceb, Dec 19 2017, 06:54:40) [MSC v.1900 64 bit (AMD64)]
 on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import torchvision
>>> import torchvision.transforms as transforms
>>> transform = transforms.Compose(
...     [transforms.ToTensor(),
...      transforms.Normalize((0.5, 0.5, 0.5), (0.5, 0.5, 0.5))])
>>> trainset = torchvision.datasets.CIFAR10(root='./data', train=True,download=T
rue, transform=transform)
Downloading https://www.cs.toronto.edu/~kriz/cifar-10-python.tar.gz to ./data\ci
far-10-python.tar.gz
You will ask me: How is this special gift label linked?
In this way:
>>> import torch
>>> trainloader = torch.utils.data.DataLoader(trainset, batch_size=4,shuffle=Tru
e, num_workers=2)
Let's take a closer look at the information in the special label.
>>> print(trainset)
Dataset CIFAR10
    Number of datapoints: 50000
    Split: train
    Root Location: ./data
    Transforms (if any): Compose(
                             ToTensor()
                             Normalize(mean=(0.5, 0.5, 0.5), std=(0.5, 0.5, 0.5)
)
                         )
    Target Transforms (if any): None
>>> print(dir(trainset))
['__add__', '__class__', '__delattr__', '__dict__', '__dir__', '__doc__', '__eq_
_', '__format__', '__ge__', '__getattribute__', '__getitem__', '__gt__', '__hash
__', '__init__', '__init_subclass__', '__le__', '__len__', '__lt__', '__module__
', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__'
, '__sizeof__', '__str__', '__subclasshook__', '__weakref__', '_check_integrity'
, 'base_folder', 'download', 'filename', 'root', 'target_transform', 'test_list'
, 'tgz_md5', 'train', 'train_data', 'train_labels', 'train_list', 'transform', '
url']
Let's look more closely at the information that can be used by the gift with the special label.
>>> print(trainloader)

>>> print(dir(trainloader))
['_DataLoader__initialized', '__class__', '__delattr__', '__dict__', '__dir__',
'__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__gt__', '__ha
sh__', '__init__', '__init_subclass__', '__iter__', '__le__', '__len__', '__lt__
', '__module__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__',
 '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', 'bat
ch_sampler', 'batch_size', 'collate_fn', 'dataset', 'drop_last', 'num_workers',
'pin_memory', 'sampler', 'timeout', 'worker_init_fn']
Beware, CIFAR10 is just one of the training databases.
About the CIFAR-10 dataset, that consists of 60,000 32x32 color images in 10 classes, with 6,000 images per class.
There are 50,000 training images (5,000 per class) and 10,000 test images.

Sunday, December 16, 2018

Fix errors when write files.

The python is a very versatile programming language.
The tutorial for today is about:
  • check the type of variables;
  • see the list error of writelines with the list output;
  • fix errors for writelines;
One good example for some errors can be this:
>>> file.writelines(paragraphs)
Traceback (most recent call last):
  File "", line 1, in 
TypeError: a bytes-like object is required, not 'str'
>>> file.writelines(paragraphs.decode('utf-8'))
Traceback (most recent call last):
  File "", line 1, in 
AttributeError: 'list' object has no attribute 'decode'
Is a common issue for list and writing file.
The result of paragraphs is a list, see:
>>> type(paragraphs)
The list can be write with te writelines into the file like this:
>>> file = open("out.txt","wb")
>>> file.writelines([word.encode('utf-8') for word in paragraphs])
The file is a open file variable and the paragraphs is a list.

Thursday, December 13, 2018

Using pytorch - a simpler perspective.

Suppose this module PyTorch is a data extravagance circuit that allows us to filter information several times, and we can decide each time we decide the final result.
A simpler perspective of how to work with PyTorch can be explained by a simple example.
It's like a Christmas baby (PyTorch) that opens a multi-packed gift until it gets the final product - the desired gift.
The opening operations of the package involve smart moves called: forward and backward passes.
The child's feedback can be called: loss and backpropagate.
In this case, the child will try to remove from his package until he is satisfied and will not be lost (loss and backpropagate functions).
To compute the backward pass for a gradient and every time we backpropagate the gradient from a variable, the gradient is accumulative instead of being reset and replaced (most of networks designs call backward multiple times).
PyTorch comes with many loss functions.
Most of examples code create a mean square error loss function and later backpropagate the gradients based on the loss.
Will you ask me if the gift is shaped? I can tell you that the gift can contain from Verge à Saint-Nicolas (unidimensional) to complex (multidimensional) structures - the most simplistic and worn out is the square one (two-dimensional matrix).
This gift is packed with magic in mathematical functions which allows the child to understand what is in the gift.
But the child is more special. He recognizes forms (matrices, shapes, simple formulas) and this allows him to open parts of the gift.
El poate roti acesta parti din cadou (mm).
The mm is a matrix multiplication.
He can see the corners he can get from the gift.
ReLU stands for "rectified linear unit" and is a type of activation function.
Mathematically, it is defined as y = max(0, x).
He can see which parts of the gift are bigger or smaller so he can understand the gift.
This clamp function clamps all elements in input into the returns[ min, max ] and returns a resulting tensor:
The clamp should only affect gradients for values outside the min and max range.
The pow function power with the exponent.
The clone returns a copy of the self tensor. The copy has the same size and data type as self.
A common example is: clamp(min=0) is exactly ReLU().
PyTorch provides ReLU and its variants through the torch.nn module.
If you run the program to look at the output, you will understand that the child has only five operations left and is already pleased with the way the gift result.
The source code is based on one example from here:
import torch 
dtype = torch.float
device = torch.device("cpu")
batch,input,hidden,output = 2,10,2,5
x = torch.randn(batch,input,device=device,dtype=dtype)
y = torch.randn(hidden,output,device=device,dtype=dtype)
w1 = torch.randn(input,hidden,device=device,dtype=dtype)
w2 = torch.randn(hidden,output,device=device,dtype=dtype)

l_r = 1e-6
for t in range(5):
 h = x.mm(w1)
 h_r = h.clamp(min=0)
 y_p = h_r.mm(w2)
 loss = (y_p - y).pow(2).sum().item()
 print("t=",t,"loss=",loss,"\n")
 g_y_p = 2.0 * (y_p -y)
 g_w2 = h_r.t().mm(g_y_p)
 g_h_r = g_y_p.mm(w2.t())
 g_h = g_h_r.clone()
 g_h[h<0 -="l_r" 0="" g_w1="" g_w2="" n="" print="" w1=",w1," w2=",w2,">
The child's result after five operations.
...
t= 4 loss= 25.40263557434082

w1= tensor([[ 1.5933,  0.3818],
        [-1.0043, -1.3362],
        [ 0.5841, -1.9811],
        [ 2.3483,  0.5748],
        [ 0.5904, -0.2521],
        [-0.6612,  2.7945],
        [ 0.4841, -0.5894],
        [-1.4434, -0.1421],
        [-1.2712, -1.4269],
        [ 0.7929,  0.2040]]) w2= tensor([[ 1.7389,  0.4337,  0.4557,  1.3704,  0
.3819],
        [ 0.2937,  0.0212, -0.4604, -1.0564, -1.5403]])

Wednesday, December 12, 2018

Using pytorch - install it on Windows OS.

A few days ago I install the pytorch on my Windows 8.1 OS and today I will able to install on Fedora 29 distro.
I will try to make a series of pytorch tutorials with Linux and Windows OS on my blogs.
If you want to install it on Fedora 29 you need to follow my Fedora blog post.
For installation on Windows OS, you can read the official webpage.
Because I don't have a new CUDA GPU, the only one video card is an NVIDIA video card 740M on my laptop and my Linux is an Intel onboard video card, I''m not able to solve issues with CUDA and pytorch.
Anyway, this will be a good start to see how to use pytorch.
Let's start the install into default way on Scripts folder from my python version 3.6.4 folder installation.
C:\Python364\Scripts>pip3 install https://download.pytorch.org/whl/cpu/torch-1.0
.0-cp36-cp36m-win_amd64.whl
Collecting torch==1.0.0 from https://download.pytorch.org/whl/cpu/torch-1.0.0-cp
36-cp36m-win_amd64.whl
  Downloading https://download.pytorch.org/whl/cpu/torch-1.0.0-cp36-cp36m-win_am
d64.whl (71.0MB)
    100% |████████████████████████████████| 71.0MB 100kB/s
Installing collected packages: torch
  Found existing installation: torch 0.4.1
    Uninstalling torch-0.4.1:
      Successfully uninstalled torch-0.4.1
Successfully installed torch-1.0.0

C:\Python364\Scripts>pip3 install torchvision
After I install the pytorch python module I import the pytorch and torchvision python modules.
First, as I expected the CUDA feature:
>>> import torch
>>> torch.cuda.is_available()
False
Let's make another test with pytorch:
>>> x = torch.rand(76, 79)
>>> x.size()
torch.Size([76, 79])
>>> print(x)
tensor([[0.1981, 0.3841, 0.9276,  ..., 0.3753, 0.7137, 0.7702],
        [0.8202, 0.9564, 0.5590,  ..., 0.0914, 0.4983, 0.7163],
        [0.0864, 0.4588, 0.0669,  ..., 0.3939, 0.0318, 0.8650],
        ...,
        [0.9028, 0.8431, 0.8592,  ..., 0.3825, 0.2537, 0.7901],
        [0.2055, 0.3003, 0.8085,  ..., 0.0724, 0.9226, 0.9559],
        [0.3671, 0.1178, 0.3837,  ..., 0.7181, 0.5704, 0.9268]])
>>> torch.tensor([[1., -1.], [1., -1.]])
tensor([[ 1., -1.],
        [ 1., -1.]])
>>> torch.zeros([1, 4], dtype=torch.int32)
tensor([[0, 0, 0, 0]], dtype=torch.int32)
>>> torch.zeros([2, 4], dtype=torch.int32)
tensor([[0, 0, 0, 0],
        [0, 0, 0, 0]], dtype=torch.int32)
>>> torch.zeros([3, 4], dtype=torch.int32)
tensor([[0, 0, 0, 0],
        [0, 0, 0, 0],
        [0, 0, 0, 0]], dtype=torch.int32)
You can make many tests and check your instalation.
This is a screenshot with all features show by dir with pytorch and torchvision:

Friday, December 7, 2018

Python Qt5 : simple checkbox example.

Today we created a simple tutorial about QCheckBox and QLabel.
The purpose of this tutorial is to use QCheckBox in a GUI interface.
When we check QCheckBox, this will change the text from a QLabel.
The variables used by QCheckBox are my_checkbox and my_label for QLabel.
The result of my source code is this:

Let's see the source code:
# -*- coding: utf-8 -*-
"""
@author: catafest
"""
import sys
from PyQt5.QtCore import Qt
from PyQt5.QtWidgets import QWidget, QCheckBox, QLabel, QApplication

class MyCheckBox(QWidget):
 def __init__(self):
  super().__init__()
 
  my_checkbox = QCheckBox("Check this , see result", self)
  my_checkbox.move(50,60)
  my_checkbox.stateChanged.connect(self.change_my_option)
  

  self.my_label = QLabel("You can visit free-tutorial.org ", self)
  self.my_label.move(50,30)

  #self.my_label.setAlignment(Qt.AlignCenter)
  
  self.setGeometry(420,420,640,100)
  self.setWindowTitle("free-tutorials.org PyQt5 ChecBox ")
  

  
 def change_my_option(self, state):
  if state  == Qt.Checked:
   self.my_label.setText("Thank's by free-tutorial.org")
  else:
   self.my_label.setText("You can visit free-tutorial.org")
   
if __name__ == '__main__':
 app = QApplication(sys.argv)
 win = MyCheckBox()
 win.show()
 sys.exit(app.exec_())

Wednesday, December 5, 2018

PySide2 and PyQt versions.

A short intro about this python module named PySide2 can be found on the Wikipedia webpage.
The purpose of this tutorial is to introduce concepts about licenses and develop python programs using ergonomic design interfaces with PySide2 and PyQt versions.

PySide2 is a Python binding of the cross-platform GUI toolkit Qt, currently developed by The Qt Company under the Qt for Python project. It is one of the alternatives to the standard library package Tkinter.
...
PySide was released under the LGPL in August 2009 by Nokia,[1] the former owners of the Qt toolkit, after Nokia failed to reach an agreement with PyQt developers Riverbank Computing[7] to change its licensing terms to include LGPL as an alternative license.
...


Now about the LGPL software license:

The GNU Lesser General Public License (LGPL) is a free software license published by the Free Software Foundation (FSF). The license allows developers and companies to use and integrate software released under the LGPL into their own (even proprietary) software without being required by the terms of a strong copyleft license to release the source code of their own components.

I wrote in the past about PySide and you can find on this blog or on my website.
Let's start installing Python using pip3.6.
C:\Python364>cd Scripts

C:\Python364\Scripts>pip3.6.exe install PySide2
Collecting PySide2
  Downloading https://files.pythonhosted.org/packages/10/ba/7448ec862655c356ade2
2351ed46c9260773186c37ba0d8ceea1ef8c7515/PySide2-5.11.2-5.11.2-cp35.cp36.cp37-no
ne-win_amd64.whl (128.7MB)
    100% |████████████████████████████████| 128.7MB 44kB/s
Installing collected packages: PySide2
Successfully installed PySide2-5.11.2
The PySide2 python module is another way to connect Qt with Python modules.
You can take a look at this python module at Qt website .
The source code is more simple but this can put the development in trouble if you try to follow the PyQt way.
Let's see a simple example. I create the main window for this example.

The layout of this window named main_layout is split into two: secondary_splitter_1 and secondary_splitter_2.
Into this, I add for each area the defined class named SecondaryWindow.
The four variables for this SecondaryWindow class are named like secondary_window_1, secondary_window_2, secondary_window_3 and secondary_window_4.
Interface programming with PySide2 and PyQt keeps a classic form of statements and then structured implementations. It seems simpler to create interfaces with PySide, but the development and community interest seems to be attracted to PyQt.
In both cases, the programming speed in the python programming language is required.
Error management is simpler and more limited in PySide2. I have noticed PyQt essential changes in developing even more advanced versions (see PyQt4 and PyQt5).
Let's see the source code:
import sys
from PySide2 import QtGui, QtCore, QtWidgets
from PySide2.QtGui import *
from PySide2.QtCore import *
from PySide2.QtWidgets import *

class SecondaryWindow(QtWidgets.QWidget):

    def __init__(self, label, parent=None):
        super(SecondaryWindow, self).__init__(parent)

        self.label = QtWidgets.QLabel(label, parent=self)
        self.label.setAlignment(QtCore.Qt.AlignCenter)
        self.label.setStyleSheet("QLabel {font-size:18px;color:blue}")

        self.main_layout = QtWidgets.QVBoxLayout()
        self.main_layout.addWidget(self.label)
        self.setLayout(self.main_layout)

class MainWindow(QtWidgets.QWidget):

    def __init__(self, parent=None):
        super(MainWindow, self).__init__(parent)

        self.secondary_window_1 = SecondaryWindow("1", parent=self)
        self.secondary_window_2 = SecondaryWindow("2", parent=self)
        self.secondary_window_3 = SecondaryWindow("3", parent=self)
        self.secondary_window_4 = SecondaryWindow("4", parent=self)

        self.secondary_splitter_1 = QtWidgets.QSplitter(QtCore.Qt.Horizontal, parent=self)
        self.secondary_splitter_1.addWidget(self.secondary_window_1)
        self.secondary_splitter_1.addWidget(self.secondary_window_2)

        self.secondary_splitter_2 = QtWidgets.QSplitter(QtCore.Qt.Horizontal, parent=self)
        self.secondary_splitter_2.addWidget(self.secondary_window_3)
        self.secondary_splitter_2.addWidget(self.secondary_window_4)

        self.main_splitter = QtWidgets.QSplitter(QtCore.Qt.Vertical, parent=self)
        self.main_splitter.addWidget(self.secondary_splitter_1)
        self.main_splitter.addWidget(self.secondary_splitter_2)

        self.main_layout = QtWidgets.QVBoxLayout()
        self.main_layout.addWidget(self.main_splitter)
        self.setLayout(self.main_layout)

        self.setWindowTitle("PySide2 example")
        self.resize(220, 220)

if __name__ == "__main__":
    app = QApplication(sys.argv)
    main_window = MainWindow()
    main_window.show()
    sys.exit(app.exec_())

Thursday, November 29, 2018

Python Qt5 : submenu example.

Using my old example I will create a submenu with PyQt5.
First, you need to know the submenu works like the menu.
Let's see the result:

The source code is very simple:
# -*- coding: utf-8 -*-
"""
@author: catafest
"""
import sys
from PyQt5.QtWidgets import QMainWindow, QAction, qApp, QApplication, QDesktopWidget, QMenu
from PyQt5.QtGui import QIcon

class Example(QMainWindow):
    #init the example class to draw the window application    
    def __init__(self):
        super().__init__()    
        self.initUI()
    #create the def center to select the center of the screen         
    def center(self):
        # geometry of the main window
        qr = self.frameGeometry()
        # center point of screen
        cp = QDesktopWidget().availableGeometry().center()
        # move rectangle's center point to screen's center point
        qr.moveCenter(cp)
        # top left of rectangle becomes top left of window centering it
        self.move(qr.topLeft())
    #create the init UI to draw the application
    def initUI(self):               
        #create the action for the exit application with shortcut and icon
        #you can add new action for File menu and any actions you need
        exitAct = QAction(QIcon('exit.png'), '&Exit', self)        
        exitAct.setShortcut('Ctrl+Q')
        exitAct.setStatusTip('Exit application')
        exitAct.triggered.connect(qApp.quit)
        #create the status bar for menu 
        self.statusBar()
        #create the menu with the text File , add the exit action 
        #you can add many items on menu with actions for each item
        menubar = self.menuBar()
        fileMenu = menubar.addMenu('&File')
        fileMenu.addAction(exitAct)
        
        # add submenu to menu 
        submenu = QMenu('Submenu',self)

        # some dummy actions
        submenu.addAction('Submenu 1')
        submenu.addAction('Submenu 2')
           
        # add to the top menu
        menubar.addMenu(submenu)
        #resize the window application 
        self.resize(640, 480)
        #draw on center of the screen 
        self.center()
        #add title on windows application 
        self.setWindowTitle('Simple menu')
        #show the application
        self.show()
        #close the UI class
        
if __name__ == '__main__':
    #create the application 
    app = QApplication(sys.argv)
    #use the UI with new  class
    ex = Example()
    #run the UI 
    sys.exit(app.exec_())

Monday, November 19, 2018

Using Google Classroom API with python.

Today I read and test Google API with the Python programming language.
You can find a good example here.
The example shows how to read with Google Classroom API, v1.
This example can be used as a default example if you want to use googlescopes.
The Google documentation tells us:
This document lists the OAuth 2.0 scopes that you might need to request to access Google APIs, depending on the level of access you need. Sensitive scopes require review by Google and have a sensitive indicator on the Google Cloud Platform (GCP) Console's OAuth consent screen configuration page. Many scopes overlap, so it's best to use a scope that isn't sensitive. For information about each method's scope requirements, see the individual API documentation.
The script use credentials.json file created by the Google project in the folder with the python script.
The script creates automatically when the authorization flow completes a token.json file.
The control of the project can be used with the Google Cloud Console.
The result of the example script can be seen in the next image:

Friday, November 16, 2018

Python Qt5 : setStyleSheet example.

Today I will show you how to style the PyQt5 widgets and create a good looking application interface.
The main goal of this tutorial is to see where you can use the style issue.
I used just one edit and one button to have a simple example.
The result of my example is this:

The example start with a simple application with QPushButton, QLineEdit.
Is more simple to use a class for the button because we need to create a different style for each action: enterEvent or leaveEvent and so on.
You can see I used QFont to change the font from button.
This class is named Push_button and will be used like any QPushButton from default PyQt5 examples.
We can do this for any widget and change it with setStyleSheet.
Another part of the code is for QLineEdit.
This can be changed easily with setStyleSheet, first with the default of this and make other changes when you need.
The source code has an QGridLayout to help us to align the widgets.
Let's see the source code:
from PyQt5 import QtWidgets, QtGui, QtCore
from PyQt5.QtCore import pyqtSignal

font_button = QtGui.QFont()
font_button.setFamily("Corbel")
font_button.setPointSize(10)
font_button.setWeight(100)

class Push_button(QtWidgets.QPushButton):
    
    def __init__(self, parent=None):
        super(Push_button, self).__init__(parent)
        self.setMouseTracking(True)
        self.setStyleSheet("margin: 1px; padding: 10px; \
      background-color: \
                           rgba(255,255,0,255); \
                           color: rgba(0,0,0,255); \
                           border-style: solid; \
                           border-radius: 4px; border-width: 3px; \
                           border-color: rgba(0,0,0,255);")

    def enterEvent(self, event):
        if self.isEnabled() is True:
            self.setStyleSheet("margin: 10px; padding: 10px; \
          background-color: \
                               rgba(255,255,0,255); \
                               color: rgba(0,0,10,255); \
                               border-style: solid; \
                               border-radius: 8px; \
                               border-width: 1px; \
                               border-color: \
                               rgba(0,0,100,255);")
        if self.isEnabled() is False:
            self.setStyleSheet("margin: 10px; padding: 10px; \
          background-color: \
                               rgba(255,255,0,255); \
                               color: rgba(0,0,10,255); \
                               border-style: solid; \
                               border-radius: 8px; \
                               border-width: 1px; \
                               border-color: \
                               rgba(0,0,100,255);")

    def leaveEvent(self, event):
        self.setStyleSheet("margin: 10px; padding: 10px; \
                           background-color: rgba(0,0,0,100); \
                           color: rgba(0,0,255,255); \
                           border-style: solid; \
                           border-radius: 8px; border-width: 1px; \
                           border-color: rgba(0,50,100,255);")


class QthreadApp(QtWidgets.QWidget):
    sig = pyqtSignal(str)
    def __init__(self, parent=None):
        QtWidgets.QWidget.__init__(self, parent)
        self.setWindowTitle("PyQt5 style application")
        self.setWindowIcon(QtGui.QIcon("icon.png"))
        self.setMinimumWidth(resolution.width() / 3)
        self.setMinimumHeight(resolution.height() / 2)
        self.setStyleSheet("QWidget { \
                           background-color: rgba(0,0,100,250);} \
                           QScrollBar:horizontal {width: 1px; \
                           height: 1px; \
                           background-color: rgba(0,100,255,0);} \
                           QScrollBar:vertical {width: 1px; \
                           height: 10px; \
                           background-color: rgba(0,41,59,255);}")
        self.linef = QtWidgets.QLineEdit(self)
        self.linef.setPlaceholderText("Input text ...")
        self.linef.setStyleSheet("margin: 10px; padding: 10px; \
                                 background-color: \
                                 rgba(0,0,0,255);\
                                 color: rgba(255,0,0,255); \
                                 border-style: solid; \
                                 border-radius: 15px; \
                                 border-width: 1px; \
                                 border-color: \
                                 rgba(255,255,255,255);")
        self.my_button = Push_button(self)
        self.my_button.setText("Blue")
        self.my_button.setFixedWidth(72)
        self.my_button.setFont(font_button)
        self.my_grid = QtWidgets.QGridLayout()
        self.my_grid.addWidget(self.linef, 0, 0, 1, 220)
        self.my_grid.addWidget(self.my_button, 0, 220, 1, 1)
        self.my_grid.setContentsMargins(8, 8, 8, 8)
        self.setLayout(self.my_grid)

if __name__ == "__main__":
    import sys
    app = QtWidgets.QApplication(sys.argv)
    desktop = QtWidgets.QApplication.desktop()
    resolution = desktop.availableGeometry()
    myapp = QthreadApp()
    myapp.setWindowOpacity(0.95)
    myapp.show()
    myapp.move(resolution.center() - myapp.rect().center())
    sys.exit(app.exec_())
else:
    desktop = QtWidgets.QApplication.desktop()
    resolution = desktop.availableGeometry()

Monday, November 12, 2018

Python Qt5 : QCalendarWidget example.

This tutorial is about QCalendarWidget.
Use a default application and add this widget.
You can change and get the date from the widget calendar like any widget.
The result of this source code is this result:

This is the source code for QCalendarWidget example:
import sys
from PyQt5 import *
from PyQt5.QtWidgets import QApplication, QCalendarWidget, QWidget, QLabel
from PyQt5.QtCore import *
from PyQt5.QtGui import *

class Example(QWidget):
   def __init__(self):
      super(Example, self).__init__()
      self.initUI()
   def initUI(self):
      my_calendar = QCalendarWidget(self)
      my_calendar.setGridVisible(True)
      my_calendar.move(10, 20)
      my_calendar.clicked[QDate].connect(self.show_date)
      self.my_label = QLabel(self)
      date = my_calendar.selectedDate()
      self.my_label.setText(date.toString())
      self.my_label.move(10, 220)
      self.setGeometry(100,100,320,270)
      self.setWindowTitle('Calendar')
      self.show()
   def show_date(self, date):
      self.my_label.setText(date.toString())

def main():
   app = QApplication(sys.argv)
   ex = Example()
   sys.exit(app.exec_())
if __name__ == '__main__':
   main()

Saturday, November 10, 2018

Python Qt5 : QTabWidget example.

Today I test the QTabWidget with an simple example.
The source code uses the QTabWidget and create two Tab: FirstTab and TabTwo.
I add for each tab two labels: tab_one_label_one, tab_one_label_two,tab_two_label_one and tab_two_label_two.
For layouts, I used: vboxLayout with first_layout and second_layout.
The result of my running code is this:

The rest of the source code is simple:
import sys
from PyQt5.QtGui import QIcon
from PyQt5.QtWidgets import QDialog, QApplication, QWidget
from PyQt5.QtWidgets import QVBoxLayout, QTabWidget, QLabel

class TabDialog(QDialog):
    def __init__(self):
        super().__init__()

        self.setWindowTitle("Tab Widget Application")
        self.setWindowIcon(QIcon("icon.png"))

        tabwidget = QTabWidget()
        tabwidget.addTab(FirstTab(), "First Tab")
        tabwidget.addTab(TabTwo(), "Second Tab")

        vboxLayout = QVBoxLayout()
        vboxLayout.addWidget(tabwidget)

        self.setLayout(vboxLayout)

class FirstTab(QWidget):
    def __init__(self):
        super().__init__()
        tab_one_label_one = QLabel("tab_one_label_one")
        tab_one_label_two = QLabel("tab_one_label_two")
        
        first_layout = QVBoxLayout()
        first_layout.addWidget(tab_one_label_one)
        first_layout.addWidget(tab_one_label_two)
        self.setLayout(first_layout)

class TabTwo(QWidget):
    def __init__(self):
        super().__init__()
        tab_two_label_one = QLabel("tab_two_label_one")
        tab_two_label_two = QLabel("tab_two_label_two")
        
        second_layout = QVBoxLayout()
        second_layout.addWidget(tab_two_label_one)
        second_layout.addWidget(tab_two_label_two)
        self.setLayout(second_layout)

if __name__ == "__main__":
    app = QApplication(sys.argv)
    tabdialog = TabDialog()
    tabdialog.show()
    app.exec()

Friday, November 9, 2018

Python Qt5 : default icons with QStyle.

This is a simple example of QStyle.
Using the QStyle can solve more issues above this example.
The QStyle can solve more problems than this example.
You can change everything in PyQt5 and Qt.
The QStyle class is an abstract base class that encapsulates the look and feel of a GUI, read here.
This is the result of a source code I used to show you how can use default icons from PyQt5.

See this source code:
import sys
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *

class Widget(QWidget):
  
    def __init__(self, parent= None):
        super(Widget, self).__init__()
        icons = [
'SP_TitleBarMinButton', 
'SP_TitleBarMenuButton', 
'SP_TitleBarMaxButton', 
'SP_TitleBarCloseButton', 
'SP_TitleBarNormalButton', 
'SP_TitleBarShadeButton', 
'SP_TitleBarUnshadeButton', 
'SP_TitleBarContextHelpButton', 
'SP_MessageBoxInformation', 
'SP_MessageBoxWarning', 
'SP_MessageBoxCritical', 
'SP_MessageBoxQuestion', 
'SP_DesktopIcon', 
'SP_TrashIcon', 
'SP_ComputerIcon', 
'SP_DriveFDIcon', 
'SP_DriveHDIcon', 
'SP_DriveCDIcon', 
'SP_DriveDVDIcon', 
'SP_DriveNetIcon', 
'SP_DirHomeIcon', 
'SP_DirOpenIcon', 
'SP_DirClosedIcon', 
'SP_DirIcon', 
'SP_DirLinkIcon', 
'SP_FileIcon', 
'SP_FileLinkIcon', 
'SP_FileDialogStart', 
'SP_FileDialogEnd', 
'SP_FileDialogToParent', 
'SP_FileDialogNewFolder', 
'SP_FileDialogDetailedView', 
'SP_FileDialogInfoView', 
'SP_FileDialogContentsView', 
'SP_FileDialogListView', 
'SP_FileDialogBack', 
'SP_DockWidgetCloseButton', 
'SP_ToolBarHorizontalExtensionButton', 
'SP_ToolBarVerticalExtensionButton', 
'SP_DialogOkButton', 
'SP_DialogCancelButton', 
'SP_DialogHelpButton', 
'SP_DialogOpenButton', 
'SP_DialogSaveButton', 
'SP_DialogCloseButton', 
'SP_DialogApplyButton', 
'SP_DialogResetButton', 
'SP_DialogDiscardButton', 
'SP_DialogYesButton', 
'SP_DialogNoButton', 
'SP_ArrowUp',  
'SP_ArrowDown', 
'SP_ArrowLeft', 
'SP_ArrowRight', 
'SP_ArrowBack', 
'SP_ArrowForward', 
'SP_CommandLink', 
'SP_VistaShield', 
'SP_BrowserReload', 
'SP_BrowserStop', 
'SP_MediaPlay', 
'SP_MediaStop', 
'SP_MediaPause', 
'SP_MediaSkipForward',
'SP_MediaSkipBackward', 
'SP_MediaSeekForward',
'SP_MediaSeekBackward', 
'SP_MediaVolume', 
'SP_MediaVolumeMuted', 
'SP_CustomBase'
            ]
        Col_size = 6
         
        layout = QGridLayout()
 
        count = 0
        for i in icons:
            select_button = QPushButton(i)
            select_button.setIcon(self.style().standardIcon(getattr(QStyle, i)))
 
            layout.addWidget(select_button, count / Col_size, count % Col_size)
            count += 1
             
        self.setLayout(layout)
         
if __name__ == '__main__':
    app = QApplication(sys.argv)
             
    dialog = Widget()
    dialog.show()
             
    app.exec_()

Thursday, November 8, 2018

Python Qt5 : QFileDialog and QTextEdit example.

This tutorial is about QFileDialog and how to use it.
First you need to create a default PyQ5 application and add your method is called by my_OpenDialog.
This will be connected to one button.
My application uses the QTextEdit to show HTML and text files.
If you try to see another file this will open badly.
I set the completeSuffix just for HTML and text.
As you know this returns the complete suffix (extension) of the file.
The content of this file is put into QTextEdit widget create and named editor_text.
This is result of using QFileDialog with python:

This is the source code with the QFileDialog example:
import sys, os
from PyQt5 import QtCore, QtWidgets

class Window(QtWidgets.QWidget):
    def __init__(self):
        super(Window, self).__init__()
        self.setWindowTitle('Text document')
        self.editor_text = QtWidgets.QTextEdit(self)

        self.button_OpenDialog = QtWidgets.QPushButton('Open', self)
        self.button_OpenDialog.clicked.connect(self.my_OpenDialog)

        layout = QtWidgets.QGridLayout(self)
        layout.addWidget(self.editor_text, 0, 0, 1, 1)
        layout.addWidget(self.button_OpenDialog, 1, 0)
        #self.handleTextChanged()

    def my_OpenDialog(self):
        path = QtWidgets.QFileDialog.getOpenFileName(
            self, 'Open file', '',
            'HTML files (*.html);;Text files (*.txt)')[0]
        if path:
            file = QtCore.QFile(path)
            if file.open(QtCore.QIODevice.ReadOnly):
                stream = QtCore.QTextStream(file)
                text = stream.readAll()
                info = QtCore.QFileInfo(path)
                if info.completeSuffix() == 'html':
                    self.editor_text.setHtml(text)
                else:
                    self.editor_text.setPlainText(text)
                file.close()

if __name__ == '__main__':
    app = QtWidgets.QApplication(sys.argv)
    window = Window()
    window.resize(640, 480)
    window.show()
    sys.exit(app.exec_())

Wednesday, November 7, 2018

Python Qt5 : QLCDNumber and QDial example.

This tutorial uses a simple example of QLCDNumber and QDial.
The steps start with create the QWidget with the QLCDNumber and QDial.
You need to set geometry for both and connect the dial with valueChanged.
Finally you need to use show to see the QWidget.
The result is show into the next screenshot:

Let see the source code:
import sys
from PyQt5.QtCore import Qt
from PyQt5.QtWidgets import (QWidget, QLCDNumber, QDial, QApplication)

class QLCDNumber_QDial(QWidget):
    def __init__(self):
        super().__init__()
        self.initUi()

    def initUi(self):
        the_lcd = QLCDNumber(self)
        the_dial = QDial(self)

        self.setGeometry(150, 100, 220, 100)
        self.setWindowTitle('QLCDNumber')

        the_lcd.setGeometry(10,10,70,70)
        the_dial.setGeometry(140,10,70,70)

        the_dial.valueChanged.connect(the_lcd.display)

        self.show()

if __name__ == '__main__':
    app = QApplication(sys.argv)
    run = QLCDNumber_QDial() 
    sys.exit(app.exec_())