Many python users have a lot of scripts.
They use some words for classes or some functions.
Sometime is hard to remember where it's this scripts.
So the easy way to do that is to find the script where is some words.
For example you need to find this : word_in_your_script
To do that just see next linux command:
$ find ~/ -type f -iname "*.py" -exec grep -l 'word_in_your_script' {} \; My question is much more complicated than intended and I will show you in this tutorial.
Most users use print or print() - if it used in python 3.
For example you can use this without import any python module.
$ python
Python 2.6.8 (unknown, Apr 14 2013, 18:10:41)
[GCC 4.3.2 20081105 (Red Hat 4.3.2-7)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> print "my text"
my text
>>> This is simple to show some strings.
What the most people don't know about print function it's the interface of stdout.write.
Let's see another example with stdout.write .
>>> sys.stdout.write(str(my text) + '\n')
File "<stdin>", line 1
sys.stdout.write(str(my text) + '\n')
^
SyntaxError: invalid syntax
>>> sys.stdout.write(str("my text") + '\n')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
NameError: name 'sys' is not defined First error tells us about function str.It's need just one arg not this my text.
The next error tells us about sys module is not import by python.
Note: This restriction can help us sometime.
Some example using stdout.write :
First is : my text example , see I add '\n' to go to the next row.
>>> import sys
>>> sys.stdout.write("my text"+'\n')
my text Let's try to change the output.
See the next image :
You can say : I can do this with print function.
>>> print "\033[0;32m"+"my text"+"\033[0m"
my text Yes! Right. Can you do this ? (see the next video)
The python script is very simple.
I used my scene with Mickey Mouse (my boy like this funny cartoon).
This is the python script.
import bpy
bpy.context.scene.render.use_border = False
bpy.context.scene.render.use_crop_to_border = False
bpy.ops.render.render()
R="Render Result"
bpy.data.images[R].save_render("/home/your_username/test_render.png") See the output image:
The next source code it's used for border and crop.
Only if you want to use it.
bpy.context.scene.render.use_border = False
bpy.context.scene.render.use_crop_to_border = False Also you can use this to set resolution percentage.
For example if you want to render just 10% of resolution use this:
bpy.context.scene.render.resolution_percentage =10 The module fnmatch provides support for Unix shell-style wildcards, which are not the same as regular expressions.
Why , because the special characters used are : * , ? , [seq] , [!seq] .
This is default example from fnmach website.
>>> for file in os.listdir('.'):
... if fnmatch.fnmatch(file, '*.txt'):
... print file
...
tableta.txt
verf.txt
a.txt
python-modules.txt
untitled.txt
resetbios.txt
>>> Now I want to show you another way to use this module.
Using Blender with multiple objects and python script can be very hard way.
For example if you have many objects or one matrix of objects create manually or with some scripts the named object is like in the next image:
Just use the fnmatch to sort this objects.
>>> import bpy
>>> import fnmatchNow get all meshes objects.
>>> all_objects = bpy.data.objectsPut names of all meshes as a list of strings.
>>> list_all_objects= [all_objects[i].name for i in range(len(all_objects))]Use the python module fnmatch to filter the name of objects.
>>> new_list_objects = fnmatch.filter(list_all_objects, 'Cube.*')]Now you can use this new list to make some change. I use print to show test the list.
>>> print(new_list_objects)
['Cube.001', 'Cube.002', 'Cube.003'The goal of fnmatch module in Blender 3D can be use one module to make list of objects and enables searching for files given a file name pattern.
It's two features in one module.
Also this python module can be used to get some
>>> regular_expression_txt = fnmatch.translate('*.txt')
>>> regular_expression_txt
'.*\\.txt\\Z(?ms)'
>>> print(regular_expression_txt)
.*\.txt\Z(?ms)Just remove \Z(?ms) and use it.
I try to use some regular expression and seam working well.
Just see the next source code:
>>> text='0123456789'
>>> reverse_text=text[::-1]
>>> print reverse_text
9876543210
>>> A fractal is a mathematical set that has a fractal dimension that usually exceeds its topological dimension , see Fractal wikipedia.
Today I used my mind and also my python skills to make one fractal image.
I use Newton's method to make all points and PIL python module to save the result.
Let's see the source code and comments.
from PIL import Image
#size of image
imgx = 600
imgy = 400
#make image buffer
image = Image.new("RGB", (imgx, imgy))
# area of fractal
xa = -2.0
xb = 2.0
ya = -2.0
yb = 2.0
#define constants
max_iterations = 10 # max iterations allowed
step_derivat = 0.002e-1 # step size for numerical derivative
error = 5e-19 # max error allowed
# function will generate the newton fractal
def f(z): return z * z + complex(-0.31,0.031)
# draw derivate fractal for each y and x
for y in range(imgy):
zy = y * (yb - ya)/(imgy - 1) + ya
for x in range(imgx):
zx = x * (xb - xa)/(imgx - 1) + xa
z = complex(zx, zy)
for i in range(max_iterations):
# make complex numerical derivative
dz = (f(z + complex(step_derivat, step_derivat)) - f(z))/complex(step_derivat,step_derivat)
# Newton iteration see wikipedia
z0 = z - f(z)/dz
# stop to the error
if abs(z0 - z) < error:
break
z = z0
#I use modulo operation expression to do RGB colors of the pixels
image.putpixel((x, y), (i % 8 * 16, i % 4 * 32,i % 2 * 64))
#save the result
image.save("fractal.png", "PNG") This is the final result of Newton fractal image:
The new version : PP 1.6.4 is released and working well.
What is PP python module?
PP is a python module which provides mechanism for parallel execution of python code on SMP and clusters.
SMP - systems with multiple processors or cores;
clusters - computers connected via network;
Read more Parallel Python.
The python module Flask is a small web framework.
Install the module using pip.
(my_new_env)[free-tutorials@free-tutorials ~]$ pip install Flask
Downloading/unpacking Flask
Downloading Flask-0.9.tar.gz (481kB): 481kB downloaded
Running setup.py egg_info for package Flask
warning: no files found matching '*' under directory 'tests'
...
...
Successfully installed Flask Werkzeug Jinja2
Cleaning up... Create the next python script and save as : flask-web.py .
from flask import Flask
app = Flask(__name__)
@app.route('/')
def hello_world():
return 'Hello World!'
if __name__ == '__main__':
app.run() Run the python script:
(my_new_env)[free-tutorials@free-tutorials ~]$ python flask-web.py
* Running on http://127.0.0.1:5000/
127.0.0.1 - - [25/Jan/2013 00:10:35] "GET / HTTP/1.1" 200 -
127.0.0.1 - - [25/Jan/2013 00:10:36] "GET /favicon.ico HTTP/1.1" 404 -
127.0.0.1 - - [25/Jan/2013 00:10:36] "GET /robots.txt HTTP/1.1" 404 -
127.0.0.1 - - [25/Jan/2013 00:10:36] "GET /favicon.ico HTTP/1.1" 404 -
127.0.0.1 - - [25/Jan/2013 00:10:36] "GET /robots.txt HTTP/1.1" 404 - You will see something like this:
Also you can try the quickstart tutorial here.
Use pip and virtualenv and you can make sandboxed Python development environments.
With this tools such as pip and virtualenv you have total control over the development environment.
Why? Because if your project is developed by a team with mutiple developers then they prefer having exactly replicated environments.
Let's try some simple example commands:
1. Start your environment ( in my case is: my_new_env ).
[free-tutorials@free-tutorials ~]$ python virtualenv.py my_new_env
New python executable in my_new_env/bin/python
Installing setuptools..................done.
Installing pip.............done. Activate your environment ( in my case is: my_new_env ).
[free-tutorials@free-tutorials ~]$ . my_new_env/bin/activate Let's see the pip --help command :
(my_new_env)[free-tutorials@free-tutorials ~]$ pip --help
Usage: pip COMMAND [OPTIONS]
--version show program's version number and exit
-h, --help Show help
-v, --verbose Give more output
-q, --quiet Give less output
--log <filename> Log file where a complete (maximum verbosity)
record will be kept
--proxy <proxy> Specify a proxy in the form
user:passwd@proxy.server:port. Note that the
user:password@ is optional and required only if
you are behind an authenticated proxy. If you
provide user@proxy.server:port then you will be
prompted for a password.
--timeout <seconds> Set the socket timeout (default 15 seconds)
--exists-action <exists_action>
Default action when a path already exists. Use
this option more than one time to specify
another action if a certain option is not
available. Choices: (s)witch, (i)gnore, (w)ipe,
(b)ackup
Commands available:
bundle: Create pybundles (archives containing multiple packages)
freeze: Output all currently installed packages (exact versions) to stdout
help: Show available commands
install: Install packages
search: Search PyPI
uninstall: Uninstall packages
unzip: Unzip individual packages
zip: Zip individual packages Now we will use freeze and install.
I will list all the pip packages used in my virtual environment.
(my_new_env)[free-tutorials@free-tutorials ~]$ pip freeze -l
PyOpenGL==3.0.2
PyOpenGL-accelerate==3.0.2 Put all the output in my_packages.txt file.
Install my packages from my_packages.txt .
(my_new_env)[free-tutorials@free-tutorials ~]$ pip install -r my_packages.txt
Requirement already satisfied (use --upgrade to upgrade): PyOpenGL==3.0.2 in
./my_new_env/lib/python2.7/site-packages (from -r my_packages.txt (line 1))
Requirement already satisfied (use --upgrade to upgrade): PyOpenGL-accelerate==3.0.2 in
./my_new_env/lib/python2.7/site-packages (from -r my_packages.txt (line 2))
Cleaning up... Let's try now to find one python module : opencv .
(my_new_env)[free-tutorials@free-tutorials ~]$ pip search opencv
remotecv - remotecv is an OpenCV server for facial and
feature recognition
ctypes-opencv - ctypes-opencv - A Python wrapper for OpenCV using
ctypes
pyopencv - PyOpenCV - A Python wrapper for OpenCV 2.x using
Boost.Python and NumPy
opencv-cython - An alternative OpenCV wrapper
CVtypes - Python OpenCV wrapper using ctypes
Tippy - another Toolbox for Image Processing in PYthon,
based on OpenCV
You can see where the version of python you are using installs to by running it the next python code.
>>> import sys
>>> sys.prefix
'/home/free-tutorials/my_new_env'
>>> sys.exec_prefix
'/home/free-tutorials/my_new_env' To leave your environment just type next command: $ deactivate.
I will come with new tutorials about pip and virtualenv .
See you later.
First you need to have the PIL python module and import this.
from PIL import Image
from PIL import ImageDraw
from PIL import ImageFont
from PIL import ImageFilter Next will be this function.Basically will make and return one RGBA image data type.
def make_img(image, textColor, backgroundColor):
img = image.convert("RGBA")
img.putdata([textColor if value == 0 else backgroundColor
for value in image.getdata()])
return img The next step is to set the text , font and the new image.
I use Arggotsc.ttf. You can use any TrueType font.
text = " Inca un script in python! "
font = ImageFont.truetype('Arggotsc.ttf', 55)
image = Image.new("1", font.getsize(text), '#FFF') Now we can draw, add text, resize, bur the text and finally save the image.
draw = ImageDraw.Draw(image)
draw.text((0, 0), text, font=font)
image = image.resize([i for i in image.size], Image.NEAREST)
imgText = make_img(image, (200, 200, 200), (0, 0, 0, 0))
blur_img = make_img(image, (0, 0, 0), (0, 0, 0, 0))
for i in range(3):
blur_img = blur_img.filter(ImageFilter.BLUR)
blur_img.paste(imgText, (0, 0), imgText)
blur_img.save("text-img.png") The result is:
See you later with another tutorial.
An easy_install replacement is pip.
So pip installs packages and managing Python packages.
Let's try to install packages.
$ pip install PyOpenGL_accelerate
bash: pip: command not found Install the pip package.
The recommended way to use pip is within virtualenv, since every virtualenv has pip installed in it automatically.
[free-tutorials@free-tutorials ~]$
curl -O https://raw.github.com/pypa/virtualenv/master/virtualenv.py
...
[free-tutorials@free-tutorials ~]$ python virtualenv.py my_new_env
New python executable in my_new_env/bin/python
Installing setuptools............................done.
Installing pip.....................done.
[free-tutorials@free-tutorials ~]$ . my_new_env/bin/activate
(my_new_env)[free-tutorials@free-tutorials ~]$ pip --help Let's try again with PyOpenGL and PyOpenGL_accelerate packages.
(my_new_env)[free-tutorials@free-tutorials ~]$
pip install PyOpenGL PyOpenGL_accelerate
Downloading/unpacking PyOpenGL
Downloading PyOpenGL-3.0.2.tar.gz (891kB): 891kB downloaded
Running setup.py egg_info for package PyOpenGL
....
Now we can test this two packages.First is PyOpenGL.
(my_new_env)[free-tutorials@free-tutorials ~]$ python
Python 2.7.3 (default, Dec 6 2012, 03:02:26)
[GCC 4.3.2 20081105 (Red Hat 4.3.2-7)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import OpenGL
>>> dir(OpenGL) ...and PyOpenGL_accelerate:
(my_new_env)[free-tutorials@free-tutorials ~]$ python
Python 2.7.3 (default, Dec 6 2012, 03:02:26)
[GCC 4.3.2 20081105 (Red Hat 4.3.2-7)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import OpenGL_accelerate
>>> dir(OpenGL_accelerate) This is working only on my_new_env.
That is all for now. I will try to do some examples with this packages.
The new Python 3.3.0 was released on September 29th, 2012.
It's been two weeks since it was launched last version of python and I don't have found complaints about this release.
We can read more about updates and changes made by developers here.
What I think it's more significantly to this version:
Let's see how to working the new Python 3.3.0
First download it , unzip and install it. See next:
/Python-3.3.0 $ ./configure
checking build system type... i686-pc-linux-gnu
checking host system type... i686-pc-linux-gnu
checking for --enable-universalsdk... no
checking for --with-universal-archs... 32-bit
checking MACHDEP... linux
checking for --without-gcc... The next step is ...
$ make all And finally ...
# su
# ./python setup.py build
running build
running build_ext
INFO: Can't locate Tcl/Tk libs and/or headers
Python build finished, but the necessary bits to build these modules were not found:
_bz2 _dbm _gdbm
_lzma _sqlite3 _ssl
_tkinter readline
To find the necessary bits, look in setup.py in detect_modules() for the module's name. I will use it without this modules, until I find a way to fix it.
$ ./python
Python 3.3.0 (default, Oct 14 2012, 21:42:00)
[GCC 4.4.1] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>>
>>> import ipaddress They are two examples of sequence data types in python.
Today I will tell about tuples.
A tuple consists of a number of values separated by commas.
The biggest problem is when we do not know the number of these values or type.
Let me illustrate with a function that returns a tuple.
This is a known tuple but we will use like an unknown tuple.
Let's see the python code and some errors:
>>> import sys
>>> if hasattr(sys, 'version_info'):
... print sys.version_info()
...
Traceback (most recent call last):
File "<stdin>", line 2, in <module>
TypeError: 'tuple' object is not callable Is very correct to got this error.
And the result using the print function:
>>> if hasattr(sys, 'version_info'):
... print "%s" % str(sys.version_info)
...
(2, 6, 4, 'final', 0) >>> if hasattr(sys, 'version_info'):
... sys.stderr.write("%s" % str(sys.version_info))
...
(2, 6, 4, 'final', 0)>>> or if you can use the repr function.
>>> if hasattr(sys, 'version_info'):
... sys.stderr.write("%s" % repr(sys.version_info))
...
(2, 6, 4, 'final', 0)>>> The official Python documentation says __repr__ is used to compute the “official” string representation of an object and __str__ is used to compute the “informal” string representation of an object.
In my opinion , the correct way it's to use repr. For example:
>>> import datetime
>>> today = datetime.datetime.now()
>>> str(today)
'2012-10-02 22:45:57.634977'
>>> repr(today)
'datetime.datetime(2012, 10, 2, 22, 45, 57, 634977)' As we see all values from tuples it's show.
You can customize Vim for editing a specific file.
In this case is our python script files.
To do that you can use modelines, or auto commands, or filetype plugins.
For example , if you want to see the number on rows then just set the boolean number option to true.
set number
The keys PageUp and PageDown are mapped to Ctr+U and Ctr+D.
The next changes of the vimrc file will move cursor only by half of screen.
map <PageUp> <C-U>
map <PageDown> <C-D>
imap <PageUp> <C-O><C-U>
imap <PageDown> <C-O><C-D> To move the cursor to the end of the screen they have to be triggered twice:
map <PageUp> <C-U><C-U>
map <PageDown> <C-D><C-D>
imap <PageUp> <C-O><C-U><C-O><C-U>
imap <PageDown> <C-O><C-D><C-O><C-D> Then you can add next line to prevent the cursor from changing the current column when jumping to other lines within the window.
set nostartofline To add some lines on your python file.
For example many python files start with this:
#!/usr/bin/env python
#-*- coding: utf-8 -*-
Just add the next line in your vimrc file.
:iabbrev newpy #!/usr/bin/env python <cr>#-*- coding: utf-8 -*- On your first line from your python file in the insert mode , write newpy and press Enter key.
Also will be a good idea to take a look at the official .vimrc for following PEP 7 & 8 conventions.
...and the result of this changes.
You need to use mercurial.
Mercurial is a free, distributed source control management tool.
It is mainly implemented using the Python programming language and C.
To use it , just see the next command.
# hg clone https://vim.googlecode.com/hg/ vim
requesting all changes
adding changesets
adding manifests
adding file changes
added 3831 changesets with 24526 changes to 2566 files (+2 heads)
updating working directory
2385 files updated, 0 files merged, 0 files removed, 0 files unresolved
Go to vim folder.
# cd vim/src/ Use configure to builds a Makefile file.
src # ./configure --enable-pythoninterp --with-features=huge --prefix=$HOME/opt/vim
configure: creating cache auto/config.cache
checking whether make sets $(MAKE)... yes
checking for gcc... gcc
checking whether the C compiler works... yes
... The next commands make builds the program and make install to install the program.
src # make && make install
mkdir objects
... Now let's try to make working well.
src # mkdir -p $HOME/bin
src # cd $HOME/bin
bin # ls
vim
bin # ln -s $HOME/opt/vim/bin/vim
bin # ls
vim
bin # which vim
/usr/bin/vim
bin # vim --version
VIM - Vi IMproved 7.2 (2008 Aug 9, compiled Sep 21 2009 11:22:49)
Included patches: 1-245 If you read all the output , will see something like this:
+profile +python +quickfix The main goal is to use vimrc.
For example you cand do this.
" Wrapping and tabs spaces.
set tw=78 ts=4 sw=4 sta et sts=4 ai
" Update syntax highlighting.
let python_highlight_all = 1
" Create smart indenting
set smartindent cinwords=if,elif,else,for,while,try,except,finally,def,class
" Auto completion using ctrl-space
set omnifunc=pythoncomplete#Complete
inoremap <nul> <C-x><C-o> With just few lines can change and improve your work.
There're situations when we want to compile the python script.
In this case , we have a python script named your_script.py.
The next script code will make one new your_script.pyc file.
import py_compile
py_compile.compile('your_script.py') Note: this will hide the python code, but some strings can be view.
For example , if you use this in your_script.py.
print 'This is a string' The string This is a string can be show in pyc file.
Today I show you how to make Voronoi diagram using python.
I use this to make textures for underwater.
This is just one example. But you can improve to control all cells of voronoi diagram.
The theory say:
In mathematics, a Voronoi diagram is a special kind of decomposition of a metric space, determined by distances to a specified family of objects (subsets) in the space. These objects are usually called the sites or the generators...Source : wikipedia.
I used the euclidean distance to make the Voronoi diagram because it's the most familiar case.
About wikipedia - Euclidean_distance: In mathematics, the Euclidean distance or Euclidean metric is the "ordinary" distance between two points that one would measure with a ruler, and is given by the Pythagorean formula...
My python script use the next python modules:
PIL - this allow me to use image functions.
random - this module give me... random numbers.
math - some math functions.
Let's see the source code :
from PIL import Image
import random
import math
Now I make the function named gen_voronoi.
This take the height and width of the output image and the number of cells.
The function has some random variables for red , green , blue - nr,ng,nb.
The function hypot is not accessible directly so we need to import math module and using math static object.
The return value is the Euclidean norm : sqrt(x*x + y*y).
def gen_voronoi(w, h, cells):
image = Image.new("RGB", (w, h))
putpixel = image.putpixel
img_x, img_y = image.size
nx = []
ny = []
nr = []
ng = []
nb = []
for i in range(cells):
nx.append(random.randrange(img_x))
ny.append(random.randrange(img_y))
nr.append(random.randrange(256))
ng.append(random.randrange(256))
nb.append(random.randrange(256))
for y in range(img_y):
for x in range(img_x):
dmin = math.hypot(img_x-1, img_y-1)
j = -1
for i in range(cells):
d = math.hypot(nx[i]-x, ny[i]-y)
if d < dmin:
dmin = d
j = i
putpixel((x, y), (nr[j], ng[j], nb[j]))
image.save("output.png", "PNG")
image.show()
Use the function to make the output.png image.
gen_voronoi(200, 200, 55)
The result is :
This is old tutorial make long time ago by me to detect faces on photos.
If you know more about OpenCV module , then is easy to understand source code.
First I load the modules:
import opencv.cv as cv
import opencv.highgui as gui
import opencvNext I set the variables and data blocks processed some particular features of the modules loaded.
hc = cv.cvLoad("haarcascade_frontalface_default.xml")
img = gui.cvLoadImage("me.jpg",cv.CV_BGR2RGB)
storage = cv.cvCreateMemStorage(0)
cascade = cv.cvLoadHaarClassifierCascade('haarcascade_frontalface_alt.xml',cv.cvSize(1, 1))
grayscale = cv.cvCreateImage(cv.cvSize(img.width, img.height), 8, 1)
cv.cvCvtColor(img, grayscale, cv.CV_BGR2GRAY)This is part where is detect faces and save the output like a jpeg image.
faces = cv.cvHaarDetectObjects(grayscale, cascade,\
storage,1.2,2,cv.CV_HAAR_DO_CANNY_PRUNING, cv.cvSize(5, 5))
if faces:
for i in faces:
cv.cvRectangle(img, cv.cvPoint( int(i.x), int(i.y)),cv.cvPoint(int(i.x + i.width), int(i.y + i.height)),cv.CV_RGB(0, 255, 0), 3, 8, 0)
gui.cvSaveImage("faces_detected.jpg", img)
The haarcascade_frontalface_default.xml file it's from internet, but you can create one if you want.
Maybe in the next tutorial I will show how.
Let's see the result. The input image file is:
... and the result is:
Today I make a new tutorial about pstats python module.
The pstats module is a statistics browser for reading and examining profiler program.
This is provided in the modules cProfile, profile and pstats.
Because it's a long tutorial with long row , I put this tutorial on my tutorials website.
You can find it here on Python section.
$mkdir test-dj
$cd test-dj/django-django-1.4-919-ge57338f.zip
Python-3.2.3.tar.bz2$tar xvjf Python-3.2.3.tar.bz2 $cd Python-3.2.3
$./configure
$make all
$sudo make altinstall
# python3.2 setup.py install $ whereis python3
python3: /usr/lib/python3.0 /usr/local/bin/python3.2m-config
/usr/local/bin/python3.2 /usr/local/bin/python3.2m
/usr/local/lib/python3.2python3.2
python3.2m
python3.2m-config * --with-pydebug (flag: d)
* --with-pymalloc (flag: m)
* --with-wide-unicode (flag: u)
$unzip django-django-1.4-919-ge57338f.zip$cd django-django-e57338f/
# python3.2 setup.py install # python3.2
Python 3.2.3 (default, Aug 24 2012, 19:24:21)
[GCC 4.4.1] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import django
>>> print(django.get_version())
1.5
>>> The platform module includes the tools to take some infos about operating system, and hardware platform where a program is running.
import platform
dir(platform)Show all about this module.
Also you can use the help.
help(platform)Let's try another
print platform.win32_ver()
('', '', '', '')So is not Windosw OS.
print platform.system()
LinuxCan be 'Linux', 'Windows' or 'Java' ...
print platform.version()Show you the system's release version ( can be Debian , Ubuntu , Fedora ).
print platform.architecture()
('32bit', 'ELF')print platform.uname()Show the infos like uname linux command.
print platform.release()Show the kernel use by system.
print platform.machine()
i686print platform.node()Show the computer's network name.
print platform.linux_distribution()Show you the linux distribution.
import os
import PIL
from PIL import Image
from PIL import ImageDraw
o=Image.new("RGBA",(192,48))
d= ImageDraw.Draw(o)
for pic in range(0,4):
strpic=str(pic)
filnam="000"+strpic+".png"
x=pic*48
img=Image.open(filnam)
o.paste(img,(0+x,0))
o.save("out.png")"""
This python script read the name of image and will create a new image with the given width and height.
$ python imgresz.py
filename input image:test.png
test.png
filename output image:test-out.jpg
->width:500
->height:400
"""
import os
import sys
from PIL import Image
from PIL import ImageDraw
filnaminp=raw_input("filename input image:")
filnamout=raw_input("filename output image:")
w=input("->width:")
h=input("->height:")
imgi=Image.open(str(filnaminp))
imgo=imgi.resize((w,h),Image.BILINEAR)
imgo.save(str(filnamout))python your_script.py
all of the code that is at indentation level 0 gets executed and functions and classes that are defined but none of their code gets ran.
If will then read :
if __name__ == '__main__'if __name__ == '__main__':
print '... is being run by itself'
else:
print '... is being run directly'In this tutorial I will show how to use wx using one class example.
This tutorial is based on some code from a previous tutorial.
Let's see the source code:
import wx
class my_gui_form(wx.Frame):
def __init__(self):
wx.Frame.__init__(self, None, -1, 'Example windows wx with Python',size=(300,150))
wx.StaticText(self, -1, 'User', (10, 20))
user = wx.TextCtrl(self, -1, '', (110, 20), (160, -1))
wx.StaticText(self, -1, 'Password', (10, 50))
passwd = wx.TextCtrl(self, -1, "", (110,50),(160, -1), style=wx.TE_PASSWORD)
conn = wx.Button(self, -1,'Connect',(10,80),(260, -1))
conn.Bind(wx.EVT_BUTTON, self.onButton)
def onButton(self, event):
button = event.GetEventObject()
print "The button's label is: " + button.GetLabel()
print "The button's name is: " + button.GetName()
if __name__ == "__main__":
app1 = wx.App(False)
frame = my_gui_form()
frame.Show()
app1.MainLoop() First , I make a class named my_gui_form.
Also I add the self on each function from this class.
I make the onButton function to working with the button Connect.
I read the event of the button with event.GetEventObject.
The link with this function is make by:
conn.Bind(wx.EVT_BUTTON, self.onButton) Source Code Optimization:
The -1 from is can replace with wx.ID_ANY.
Install wx python module using root account.
# yum install wxPython.i686 The most simple example is show bellow.
$python
Python 2.7.2 (default, Oct 27 2011, 01:36:46)
[GCC 4.6.1 20111003 (Red Hat 4.6.1-10)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import wx
>>> app1=wx.App()
>>> frame=wx.Frame(None,-1,'Example windows wx with Python')
>>> frame.Show()
True
>>> app1.MainLoop()
>>>
Let's see the result of this python script:
Let's take a look at the source code.
import wx This line of code allows us to use wx python module.
app1=wx.App() This line defines our application named app1.
A frame is a window whose size and position can be changed by the user.
Let's see:
frame=wx.Frame(None,-1,'Example windows wx with Python')
frame.Show() Finally, processing and display function in main function.
app1.MainLoop() Bellow, we can see a more complex example, where we find : labels , two editbox and one button.
The event-processing function button has not been implemented.
import wx
app1=wx.App()
frame=wx.Frame(None,-1,'Example windows wx with Python',size=(300,150))
wx.StaticText(frame, -1, 'User', (10, 20))
user = wx.TextCtrl(frame, -1, '', (110, 20), (160, -1))
wx.StaticText(frame, -1, 'Password', (10, 50))
passwd = wx.TextCtrl(frame, -1, "", (110,50),(160, -1), style=wx.TE_PASSWORD)
conn = wx.Button(frame, -1,'Connect',(10,80),(260, -1))
frame.Show()
app1.MainLoop()
Let's see the result of this python script:
I will illustrate how this working in a future tutorial.