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#+LaTeX_CLASS: beamer
#+LaTeX_CLASS_OPTIONS: [presentation]
#+BEAMER_FRAME_LEVEL: 1
#+BEAMER_HEADER_EXTRA: \usetheme{Warsaw}\usecolortheme{default}\useoutertheme{infolines}\setbeamercovered{transparent}
#+COLUMNS: %45ITEM %10BEAMER_env(Env) %10BEAMER_envargs(Env Args) %4BEAMER_col(Col) %8BEAMER_extra(Extra)
#+PROPERTY: BEAMER_col_ALL 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 :ETC
#+LaTeX_CLASS: beamer
#+LaTeX_CLASS_OPTIONS: [presentation]
#+LaTeX_HEADER: \usepackage[english]{babel} \usepackage{ae,aecompl}
#+LaTeX_HEADER: \usepackage{mathpazo,courier,euler} \usepackage[scaled=.95]{helvet}
#+LaTeX_HEADER: \usepackage{listings}
#+LaTeX_HEADER:\lstset{language=Python, basicstyle=\ttfamily\bfseries,
#+LaTeX_HEADER: commentstyle=\color{red}\itshape, stringstyle=\color{darkgreen},
#+LaTeX_HEADER: showstringspaces=false, keywordstyle=\color{blue}\bfseries}
#+TITLE:
#+AUTHOR: FOSSEE
#+EMAIL:
#+DATE:
#+DESCRIPTION:
#+KEYWORDS:
#+LANGUAGE: en
#+OPTIONS: H:3 num:nil toc:nil \n:nil @:t ::t |:t ^:t -:t f:t *:t <:t
#+OPTIONS: TeX:t LaTeX:nil skip:nil d:nil todo:nil pri:nil tags:not-in-toc
*
#+begin_latex
\begin{center}
\vspace{12pt}
\textcolor{blue}{\huge Using python modules}
\end{center}
\vspace{18pt}
\begin{center}
\vspace{10pt}
\includegraphics[scale=0.95]{../images/fossee-logo.png}\\
\vspace{5pt}
\scriptsize Developed by FOSSEE Team, IIT-Bombay. \\
\scriptsize Funded by National Mission on Education through ICT\\
\scriptsize MHRD,Govt. of India\\
\includegraphics[scale=0.30]{../images/iitb-logo.png}\\
\end{center}
#+end_latex
* Objectives
At the end of this tutorial, you will be able to ,
- Execute python scripts from command line.
- Use import in scripts.
- Import scipy and pylab modules.
- Use python standard modules and 3rd party modules.
* Pre-requisite
Spoken tutorial on -
- Using plot interactively.
- Embellishing a plot.
- Saving plots.
* Running Python script from command line
- Create a script, open text editor and type the following
: print "hello world!"
: print
- Save the script as ~hello.py~
* Running Python script from command line (cont'd)
- Run the script
: $ python hello.py
/Syntax :/ *python filename*
* Four plot problem
#+begin_latex
\begin{center}
\includegraphics[scale=0.4]{four_plot}
\end{center}
#+end_latex
* Fix ~linspace()~ problem
: from scipy import *
* Fix ~plot()~ problem
: from pylab import *
* Better way of fixing
: from scipy import linspace
instead of
: from scipy import *
~*~ means import all functions from name-space ~scipy~.
* Instead of ~*~
: from scipy import linspace, pi, sin
: from pylab import plot, legend, annotate
: from pylab import xlim, ylim, title, show
Is better than, ~from scipy import *~ \& ~from pylab import *~.
* Another Fix
#+begin_src python
import scipy
import pylab
x = scipy.linspace(-5*scipy.pi, 5*scipy.pi, 500)
pylab.plot(x, x, 'b')
pylab.plot(x, -x, 'b')
pylab.plot(x, scipy.sin(x), 'g', linewidth=2)
pylab.plot(x, x*scipy.sin(x), 'r', linewidth=3)
pylab.legend(['x', '-x', 'sin(x)', 'xsin(x)'])
pylab.annotate('origin', xy = (0, 0))
pylab.xlim(-5*scipy.pi, 5*scipy.pi)
pylab.ylim(-5*scipy.pi, 5*scipy.pi)
#+end_src
* Exercise 1
- Write a python script to plot a sine wave from
#+begin_latex
$-2\Pi$
#+end_latex
to
#+begin_latex
$2\Pi$
#+end_latex
.
* What is a module?
Module is simply a file containing Python definitions and
statements. Definitions from a module can be imported into other
modules or into the main module.
* Python standard library
Python has a very rich standard library of modules.
- Few libraries
- Math: ~math~, ~random~
- Internet access: ~urllib2~, ~smtplib~
- System, Command line arguments: ~sys~
- Operating system interface: ~os~
- regular expressions: ~re~
- compression: ~gzip~, ~zipfile~, ~tarfile~
- More information
- [[http://docs.python.org/library]]
* Summary
In this tutorial, we have learnt to,
- Run scripts from command line,
- Import modules by specifying the module name followed by
an asterisk.
- Import only the required functions from modules by specifying
the function name.
- Use python standard library.
* Evaluation
1. Which among this is correct ?
- from scipy import plot
- from numpy import plot
- from matplotlib import plot
- from pylab import plot
2. Which among these libraries is part of python standard library ?
- Mayavi
- scipy
- matplotlib
- urllib2
3. Functions ``xlim()'' and ``ylim()'' can be imported to the current
name-space as,
- from pylab import xlim, ylim
- import pylab
- from scipy import xlim, ylim
- import scipy
* Solutions
1. from pylab import plot
2. urllib2
3. from pylab import xlim, ylim
*
#+begin_latex
\begin{block}{}
\begin{center}
\textcolor{blue}{\Large THANK YOU!}
\end{center}
\end{block}
\begin{block}{}
\begin{center}
For more Information, visit our website\\
\url{http://fossee.in/}
\end{center}
\end{block}
#+end_latex
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