Python Blogs

Reportlab and Pisa

sharmavivek82

Reportlab and Pisa

PDF display or download through a web page is always an excellent idea to impress other if it's done on the fly, and Reportlab and Pisa gives you the great feature to do that.
In my case, i had a small file and using that file i have to create PDF, obviously with too many calculations and plots(Reportlab used). So, if you are using python then none other tool is as good as reportlab and Pisa.
I feel very comfortable to create HTML first and then convert it to PDF using Pisa. Here is the simple solution or you can say kind of HTML template to convert to PDF.
To understand this code, you need to go through Pisa documentation.

[code python]

import cStringIO
import ho.pisa as pisa

def convert(data, filename, open=False):
pdfFile = file(filename, "wb")
pdf = pisa.CreatePDF(
cStringIO.StringIO(data.encode("ISO-8859-1")),pdfFile)
pdfFile.close()
if not pdf.err:
pisa.startViewer(filename)

if __name__=="__main__":
HTML = """<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html;charset=iso-8859-1" />
<style type="text/css" media="all">
@page {
margin: 0.5cm;
margin-top:1.8cm;
margin-bottom: 1cm;
@frame footer {
-pdf-frame-content: footerContent;
bottom: 0.5cm;
margin-left: 0.75cm;
margin-right: 0.75cm;
height: 1cm;
}
@frame header {
-pdf-frame-content: headerContent;
top: 0.2cm;
margin-left: 0.75cm;
margin-right: 0.75cm;
height: 2cm;
}
}
.footer .head
{
position:absolute;
left:0;
top:4;
width:100%;
}
table {
-pdf-keep-in-frame-mode: shrink;
}
h1 {
page-break-before:always;
}
</style>
</head>
<body>
<div id="headerContent" class="head">
<table width="100%" height="100px" border="0" >
<tr>
<td wodth="25%"><img src="logo.gif" width="70px" height="80px"/>Company Name</td>
<td align="center" width="50%"><font face="Helvetica-Bold" size="24"> Title </font></td>
<td width="25%"><font face="Helvetica" size="4">Sub titles</font></td>
</tr>
</table>
</div><br/></br>
<h1>YOUR OTHER HTML CONTENT WILL GO HERE..........</h1><br/></br>
<h1>YOUR OTHER HTML CONTENT WILL GO HERE..........</h1><br/></br>
<h1>YOUR OTHER HTML CONTENT WILL GO HERE..........</h1><br/></br>
<div id="footerContent">
<div class="footer">
This is footer.. Page <pdf:pagenumber/>
</div>
</div>

</body>
</html>"""
convert(HTML, 'pisa_example.pdf')
[/code]

Say thanks to me if this code helps you :)

SimpleAI, Artificial Intelligence with python

machinalis

SimpleAI is an easy to use lib implementing in python many of the
artificial intelligence algorithms described on the book "Artificial
Ingelligence, a Modern Approach", from Stuart Russel and Peter Norvig.

This implementation takes some of the ideas from the Norvig's
implementation (the aima-python lib), but it's made with a more
"pythonic" approach, and more emphasis on creating a stable, modern,
and mantenible version. We are testing the majority of the lib, it's
available via pip install, has a standard repository and lib architecture,
well documented, respects the python pep8 guidelines, provides only
working code (no placeholders for future things), etc. Even the
internal code is written with readability in mind, not only the
external API.

This new release adds a few statistical classification methods to SIMPLEAI with
the intention of start replicating the machine learning aspects of aima-python.

There is a special focus in decision tree learning, where three different
methods for decision tree learning are added, with one of them following
strictly the aima pseudo-code, being particularly useful for teaching.
The other classifiers added are Naive Bayes and K-Nearest Neighbors.

This release also includes lots of tests for the classifiers, documentation,
and a few sample uses of the classifiers

http://pypi.python.org/pypi/simpleai/
https://github.com/simpleai-team/simpleai.

Algoritmo en python 3 para realizar la b�squeda A* (A estrella)

pythonista

[code python]

#!/usr/bin/python -w

# Inicializamos las listas de abiertos y cerradas en vacio

# Inicializamos todos los estados como arreglos de clave y valor,

# con sus respectivos estados vecinos como clave y el costo como valor

# Establecemos la lista de estados, para luego accederla mediante el indice

# y tambien la lista de distancias entre cada par de estados.

opened = []

closed = []

q0 = {1:5, 2:4, 3:11}

q1 = {0:5, 3:6, 4:15}

q2 = {0:4, 3:5, 4:12}

q3 = {0:11, 1:6, 2:5, 4:5}

q4 = {1:15, 2:12, 3:5}

states = [q0, q1, q2, q3, q4]

distances = [[0, 5, 4, 11, 17], [5, 0, 5, 6, 15], [4, 5, 0, 5, 12], [11, 6, 5, 0, 5], [17, 15, 12, 5, 0]]

# Funcion para obtener el camino entre 2 estados, mediante el algoritmo de busqueda A*

def get_way(start, goal):

actual = start

# "Importamos" nuestra variable global para poderla modificar localmente

global opened

# Agregamos el estado actual a la lista de estados abiertos

opened.append(actual)

finalized = False

# No terminaremos hasta que no hayamos llegado a el estado meta

while not finalized:

# Si el estado actual es igual a la meta, entonces agregamos al estado acual

# a la lista de cerrados y devolvemos la lista la cual indica nuestro camino

if actual == goal:

closed.append(actual)

return closed

else:

# Si no, tomamos todos los estados vecinos del estado actual que no se incluyen

# en la lista de estados cerrados, y los agregamos a la lista de abiertos

opened = [k for k in states[actual].keys() if k not in closed]

# Cerramos el estado actual

closed.append(actual)

# Ahora tomamos como estado actual, aquel estado vecino con el menor costo

# y distancia

actual = less_f_score(actual, opened)

# Limpiamos la lista de abiertos y realizamos una iteracion mas

opened = []

# Funcion para determinar el estado vecino con el menor costo y distancia

def less_f_score(actual, opened):

# Obtenemos la suma del costo y la distancia menor, para un conjunto de estados vecinos

less = min([states[actual][state] + distances[state][goal] for state in opened])

# Recorremos la lista de vecinos

for state in opened:

# Si la suma del costo y la distancia para un estado es igual a la menor

# entonces devolvemos dicho estado

if states[actual][state] + distances[state][goal] == less:

return state

if __name__ == "__main__":

# Ingresamos los valores para el estado inicial y el estado meta

start = input("Input the start state: ")

goal = input("Input the goal state: ")

try:

# Los convertimos a enteros

start = int(start)

goal = int(goal)

except:

print("Invalid number")

# Obtenemos el camino el cual es una lista de estados

way = get_way(start, goal)

# Imprimimos la respuesta

print("<", end = " ")

for state in way:

print(state, end = " ")

print(">")

# Terminamos

[/code]

A Heroku Python Flask website application

sookies

We have been talking about Heroku applications using Python, where we can set up Python based web hosting without the need to work around Apache to get a python based web site running. In our python website example we use the flask library instead of Apache for the server.

The simplest 'Hello World' flask application is easy to find. It is on the Heroku website as well as in documentation that can be found for the Flask modules. Nonetheless, here it is again:

[code python] from flask import Flask

app = Flask(__name__)
@app.route('/')
def hello():
return 'Hello World!' if __name__ == '__main__': app.run('') [/code]

To simplify using flask, lets just run this application on our Ubuntu computer to 127.0.0.1

To do this, we need to have the Flask library available to applications.

pip install flask

Then, all we need to do to see our 'Hello World' application is this:

python hello.py

Holy strawberries Batman! We've got a website! Does Heroku work this simply? No, the Heroku version of Hello World contains two extra lines of code, and uses the OS module for Python, so to conclude today's discussion about simple python web site applications, here is the Heroku version of Hello World.

[code python] import os from flask import Flask app = Flask(__name__) @app.route('/') def hello(): return 'Hello World!' if __name__ == '__main__': # Bind to PORT if defined, otherwise default to 5000. port = int(os.environ.get('PORT', 5000)) app.run(host='0.0.0.0', port=port)[/code]

If you don't believe me, go to the www.heroku.com website, they really deserve the credit, because I cut and pasted this example from them. Two lines of code are added to the main execution body of the example, first the variable 'port' is set with the results of an operating system call and that is provided for the app.run command.

Can you think of a way to turn this into a single line of code? If you can, you have started to read and understand Python, and hopefully look forward to our next discussion on Python Flask Heroku applications. See you later, alligator!

"Hello World!" - the pyton version

max

The python way is to do more, by doing less. So the very first python program of every chap should be:

#!/usr/bin/env python
import this

It's a statement, a goal and the dawn of enlightment - in short: pure beauty.

Python Coding Standards

ugkarthik

Coding standards is not only to avoid ugly code. It is very useful to get responses quickly.

You can see the python coding standards in PEP8.

There are many third party packages to test standards you used in your modules. Especially pylint package is very simple to use.

To install pylint follow the link http://pypi.python.org/pypi/pylint.

Examples:

Here I write two modules having same logic. First one(ws.py) is written with standards and another one(wos.py) is not having standards.

#### With Standards (ws.py) ####

"""
Test the coding standards

"""

from datetime import datetime, timedelta

def with_standard():
"""

Test the coding standards

"""

st_time = datetime.\
now()
data = {'los':30,
'san':60,
'can':80,
'New':20}
for city, provider_count in data.\
iteritems():
if (city != '' and \
provider_count < 100):
pass
end_time = (datetime.\
now() - timedelta(hours=st_time.hour,
seconds=st_time.second,
microseconds=st_time.microsecond))
print "To get response the script took %s \
(Hour:Minutes:Seconds MicroSeconds)" % (end_time.\
strftime('%H:%M:%S %f'))
return ()

if __name__ == '__main__':
with_standard()

### End of Module ###

### Without standards (wos.py) ###

from datetime import datetime,timedelta

def without_standard():
st_time = datetime.now()
data = {'los':30,'san':60,'can':80,'New':20}
for key,value in data.iteritems():
if key != '' and value < 100:
pass
end_time = datetime.now() - timedelta(hours=st_time.hour,seconds=st_time.second,microseconds=st_time.microsecond)
print "To get response the script took %s (Hour:Minutes:Seconds MicroSeconds)" %(end_time.strftime('%H:%M:%S %f'))
return ()

if __name__ == '__main__':
without_standard()

### End of Module ###

Test standards:

If we execute pylint ws.py command from command line, it will give 10.00/10 as the standards rate.

When we execute pylint wos.py command, it will give 3.85/10 as the rate.

Now you can see a huge difference between standards' rate.

So try to follow standards in your future modules :)

IDLE Easter Egg...

numbercruncher

Presented without comment, aside from the fact that this made me laugh on an otherwise frustrating day...

[code python]

import antigravity

[/code]

Update: I found an article talking about this, with a comment from the BDFL...

Workaround for Python bug: 'ascii' codec can't encode character u'\xa0' in position 111: ordinal not in range(128)

mypy

Have you ever needed to read unicode data file from Python?

If so, you know that it is harder than it sounds.

Even if you set your environment (e.g. export LANG=fr_FR.UTF8) to use utf-8 Python as of 2.7.1 still might not pick up this and will try to read file in ascii resulting in all too common: 'ascii' codec can't encode character u'\xa0' in position 111: ordinal not in range(128)

After lots of trial and error I found a workaround that works. First of all check if you have this problem by executing:

[code python]
import sys
sys.getdefaultencoding()
[/code]

if it comes back with 'ascii' then read on.

Default encoding need to be changed. However this is only possible when sys module is reloaded.

Here is a complete solution:

[code python]
import sys;
reload(sys);
sys.setdefaultencoding("utf8")
[/code]

Python-Basics

muthuvel

List of Python Software :

http://en.wikipedia.org/wiki/List_of_Python_software

Organizations Using Python :

http://wiki.python.org/moin/OrganizationsUsingPython

PYGTK?

rbwilkinson

For the application I will be using Aptana 3 as my IDE. I have used gedit but I want to wallow around in something that makes me feel more professional. I will be using PYGTK to handle my GUI needs. I would like to approach this using MVC methods. I suppose I should start with my model first. Any ideas?

File for Copying the Directory to other location which the user can specify

bharath6725

import sys

import os

import tkMessageBox

from Tkinter import *

from tkCommonDialog import Dialog

import shutil

import tkFileDialog

import win32com.client

win = Tk()

win.title("Copying the Directory to specified location")

win.geometry("600x600+200+50")

win.resizable()

src = ''

des= ''

class Copy():

def __init__(self):

def srce():

src = tkFileDialog.askdirectory(title = "The source folder is ")

textboxsrc.delete(0,END)

textboxsrc.insert(0,src)

print src

return src

textboxsrc = Entry(win, width="70")

textboxsrc.insert(0,'Enter master file name')

textboxsrc.pack()

textboxsrc.place(relx=0.40, rely=0.06, anchor=CENTER)

bu = Button(text = "Source",font = "Verdana 12 italic bold",bg = "Purple",fg= "white", command= srce)

bu.pack(fill =X, expand=YES)

bu.place(relx=0.85, rely=0.06, anchor=CENTER)

def dest():

des = tkFileDialog.askdirectory(title = "TheDestination folder is ")

textboxdes.delete(0,END)

textboxdes.insert(0,des)

print des

return des

textboxdes = Entry(win, width="70")

textboxdes.insert(0,'Enter master file name')

textboxdes.pack()

textboxdes.place(relx=0.40, rely=0.13, anchor=CENTER)

bu1 = Button(text = "Destination",font = "Verdana 12 italic",bg = "Purple",fg= "white", command= dest)

bu1.pack(fill =X, expand=YES)

bu1.place(relx=0.85, rely=0.13, anchor=CENTER)

def start():

#try:

shutil.copytree(src,des)

#except :

#tkMessageBox.showwarning("Copying file", "Error while copying\n(%s)" )

bn =Button(text = "Copy",font = "Verdana 12 italic", bg = "Purple",fg= "white",command=start)

bn.pack(fill =X, expand = YES)

bn.place(relx=0.50, rely=0.25, anchor=CENTER)

obj= Copy()

win.mainloop()

Добавление элемента в список неуникальных символов ПЕРЕД символом и ПОСЛЕ

snippets

Понадобилось в работе и помню, что пригодилось бы ранее, но просто не было времени придумать, оттестить и отдалить.

Добавление элемента в список неуникальных символов ПЕРЕД символом:

[code python]
class Before(list): def __init__(self, *args, **kwargs): super(Before, self).__init__(*args, **kwargs) self.check() def check(self): index = 0 while index != len(self): a = self[index] if a == "a": self.insert(index, "!") index += 2 else: index += 1
[/code]

Добавление элемента в список неуникальных символов ПОСЛЕ символа:

[code python]
class After(list):
def __init__(self, *args, **kwargs):
super(After, self).__init__(*args, **kwargs)

self.check()

def check(self):
for index, member in enumerate(self):
if member == "a":
self.insert(index + 1, "!")
[/code]

Timer Help Python 2.5

mike

Does anyone know how to make a Timer function in Python 2.5. Cancel or .cancel() only stops the Timer while in execution, but how do you stop the Timer or threading after execution is finished. This is what I made for a timer, but it locks up the program.

def main():
import time
import threading
global time
global threading
global stoneskinT

stoneskinT = threading.Timer(5.0, stoneskin)
stoneskinT.start()
string = raw_input ("... ")
stoneskinT.cancel()

while (string == ""):
stoneskinT = threading.Timer(5.0, stoneskin)
stoneskinT.start()
string = raw_input ("... ")
stoneskinT.cancel()

def stoneskin():
global string
global stoneskinT
print "Potion of stoneskin has worn off."
string = raw_input ("... ")
main()

Random Password Generation in Python

hayathms

Auto Password Generating In Python

Here is the code for simple auto password generating in python using any string like first name, or username or anything .

import random

def gen_random_password(string_letters):
string_letters = string_letters.replace(' ','')
string_letters = string_letters.replace('.','')
a = random.choice(string_letters)
b = random.choice(string_letters)
c = random.choice(string_letters)
d = random.choice(string_letters)
e = str(random.randint(100,500))
f = str(random.randint(500,1000))
return a+e+b+f+c+d]

And Please comment me how strong password can be generated using my above code. :)

Artist new release search program

tomsimmons

This is the first program I've written that has actually served a real purpose to me, that I use frequently. Feel free to criticize and make any suggestions or corrections, because the code is probably pretty ugly. I hope it's readable. The program searches for the newest release of whatever electronic music artist you specify from trackitdown.net. Keep in mind please, that I'm a total python noob.

#!/usr/bin/python

from urllib import urlopen

from subprocess import call

print "\n+++++++++++++++++++++++++++++++++++++++++++++++++++++"

print "Artist new release search v1.0"

print "This program utilizes www.trackitdown.net for results"

print "+++++++++++++++++++++++++++++++++++++++++++++++++++++\n"

try:

def artist_search():

try:

artist = raw_input('\nEnter artist name: ')

print "\nSearching..."

website = urlopen('http://www.trackitdown.net/search/advanced?artist=' + artist)

text = website.read()

import re

artist = re.search('Artist: <a href="/artist/([^"]+)" title="([^"]+)">([^"]+)</a>', text, re.IGNORECASE)

artist.group(1)

track = re.search('<a href="/genre/([^"]+)/track/([^"]+).html"><strong>([^"]+)</strong>', text, re.IGNORECASE)

track.group(1)

date = re.search('release date: ([^"]+)<br />', text, re.IGNORECASE)

date.group(1)

urlpreview = re.search('<a href="([^"]+).mp3"', text, re.IGNORECASE)

url = urlpreview.group(1)

except AttributeError: print '\nNo artist found! Exiting...', quit()

print "\nFound result!"

print "\n======================================"

print "Artist: " + artist.group(3)

print "Track name: " + track.group(3)

print "Release date: " + date.group(1)

print "======================================\n"

try:

print "\nPreview at: " + urlpreview.group(1) + ".mp3"

preview = raw_input('Play preview? y/n: ')

if preview == 'y' : call(['mpg123', url + ".mp3"])

if preview == 'n' : print "Exiting...", quit()

except OSError: print "Looks like you don't have mpg123 installed! Exiting...", quit()

except KeyboardInterrupt: search_again = raw_input("\nWould you like to perform another search? y/n: ")

if search_again == "n" : print 'Exiting...', quit()

if search_again == "y" : artist_search()

artist_search()

except UnboundLocalError: print "\n", artist_search()