--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/getting-started-with-functions/slides.org Wed Nov 10 18:58:11 2010 +0530
@@ -0,0 +1,289 @@
+#+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: Getting started with functions
+#+AUTHOR: FOSSEE
+#+EMAIL: info@fossee.in
+#+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
+
+# * Outline
+# - Manipulating one and multi dimensional arrays
+# - Access and change individual elements
+# - Access and change rows and columns
+# - Slicing and striding on arrays to access chunks
+# - Read images into arrays and manipulations
+# * Sample Arrays
+# #+begin_src python
+# In []: A = array([12, 23, 34, 45, 56])
+
+# In []: C = array([[11, 12, 13, 14, 15],
+# [21, 22, 23, 24, 25],
+# [31, 32, 33, 34, 35],
+# [41, 42, 43, 44, 45],
+# [51, 52, 53, 54, 55]])
+
+# #+end_src
+# * Question 1
+# Change the last column of ~C~ to zeroes.
+# * Solution 1
+# #+begin_src python
+# In []: C[:, -1] = 0
+# #+end_src
+# * Question 2
+# Change ~A~ to ~[11, 12, 13, 14, 15]~.
+# * Solution 2
+# #+begin_src python
+# In []: A[:] = [11, 12, 13, 14, 15]
+# #+end_src
+# * squares.png
+# #+begin_latex
+# \begin{center}
+# \includegraphics[scale=0.6]{squares}
+# \end{center}
+# #+end_latex
+# * Question 3
+# - obtain ~[22, 23]~ from ~C~.
+# - obtain ~[11, 21, 31, 41]~ from ~C~.
+# - obtain ~[21, 31, 41, 0]~.
+# * Solution 3
+# #+begin_src python
+# In []: C[1, 1:3]
+# In []: C[0:4, 0]
+# In []: C[1:5, 0]
+# #+end_src
+# * Question 4
+# Obtain ~[[23, 24], [33, -34]]~ from ~C~
+# * Solution 4
+# #+begin_src python
+# In []: C[1:3, 2:4]
+# #+end_src
+# * Question 5
+# Obtain the square in the center of the image
+# * Solution 5
+# #+begin_src python
+# In []: imshow(I[75:225, 75:225])
+# #+end_src
+# * Question 6
+# Obtain the following
+# #+begin_src python
+# [[12, 0], [42, 0]]
+# [[12, 13, 14], [0, 0, 0]]
+# #+end_src
+
+# * Solution 6
+# #+begin_src python
+# In []: C[::3, 1::3]
+# In []: C[::4, 1:4]
+# #+end_src
+# * Summary
+# You should now be able to --
+# - Manipulate 1D \& Multi dimensional arrays
+# - Access and change individual elements
+# - Access and change rows and columns
+# - Slice and stride on arrays
+# - Read images into arrays and manipulate them.
+
+
+* Outline
+ - Define functions
+ - Pass arguments to functions
+ - Learn about docstrings
+ - Return values from functions
+
+* Function
+ - Eliminate code redundancy
+ - Help in code reuse
+ - Subroutine
+ - relatively independent of remaining code
+
+* ~f(x)~ a mathematical function
+
+ $f(x) = x^{2}$
+
+ : f(1) -> 1
+ : f(2) -> 4
+
+* Define ~f(x)~ in Python
+ #+begin_src python
+ def f(x):
+ return x*x
+ #+end_src
+
+ - ~def~ - keyword
+ - ~f~ - function name
+ - ~x~ - parameter / argument to function ~f~
+
+* Exercise 1
+
+ Write a python function named ~cube~ which computes the cube of a given
+ number ~n~.
+
+ - Pause here and try to solve the problem yourself.
+
+* Solution
+ #+begin_src python
+ def cube(n):
+ return n**3
+ #+end_src
+
+* ~greet~ function
+
+ Function ~greet~ which will print ~Hello World!~.
+ #+begin_src python
+ def greet():
+ print "Hello World!"
+ #+end_src
+ - Call the function ~greet~
+ : In []: greet()
+ : Hello World!
+
+* Exercise 2
+
+ Write a python function named ~avg~ which computes the average of
+ ~a~ and ~b~.
+
+ - Pause here and try to solve the problem yourself.
+
+* Solution 2
+ #+begin_src python
+ def avg(a,b):
+ return (a + b)/2
+ #+end_src
+
+ - ~a~ and ~b~ are parameters
+ - ~def f(p1, p2, p3, ... , pn)~
+
+* Docstring
+
+ - Documenting/commenting code is a good practice
+ #+begin_src python
+ def avg(a,b):
+ """ avg takes two numbers as input
+ (a & b), and returns the average
+ of a and b"""
+ return (a+b)/2
+ #+end_src
+ - Docstring
+ - written in the line after the ~def~ line.
+ - Inside triple quote.
+ - Documentation
+ : avg?
+* Exercise 3
+ Add docstring to the function f.
+
+* Solution 3
+
+#+begin_src python
+ def f(x):
+ """Accepts a number x as argument and,
+ returns the square of the number x."""
+ return x*x
+#+end_src
+
+* Exercise 4
+ Write a python function named ~circle~ which returns the area and
+ perimeter of a circle given radius ~r~.
+
+* Solution 4
+#+begin_src python
+ def circle(r):
+ """returns area and perimeter of a circle given
+ radius r"""
+ pi = 3.14
+ area = pi * r * r
+ perimeter = 2 * pi * r
+ return area, perimeter
+#+end_src
+
+* ~what~
+#+begin_src python
+
+ def what( n ):
+ if n < 0: n = -n
+ while n > 0:
+ if n % 2 == 1:
+ return False
+ n /= 10
+ return True
+#+end_src
+
+* ~even_digits~
+#+begin_src python
+ def even_digits( n ):
+ """returns True if all the digits of number
+ n is even returns False if all the digits
+ of number n is not even"""
+ if n < 0: n = -n
+ while n > 0:
+ if n % 2 == 1:
+ return False
+ n /= 10
+ return True
+#+end_src
+
+* ~what~
+#+begin_src python
+ def what( n ):
+ i = 1
+ while i * i < n:
+ i += 1
+ return i * i == n, i
+#+end_src
+
+* ~is_perfect_square~
+#+begin_src python
+ def is_perfect_square( n ):
+ """returns True and square root of n,
+ if n is a perfect square, otherwise
+ returns False and the square root
+ of the next perfect square"""
+ i = 1
+ while i * i < n:
+ i += 1
+ return i * i == n, i
+#+end_src
+
+* Summary
+ - Functions in Python
+ - Passing parameters to a function
+ - Returning values from a function
+
+ - We also did few code reading exercises.
+
+* Thank you!
+#+begin_latex
+ \begin{block}{}
+ \begin{center}
+ This spoken tutorial has been produced by the
+ \textcolor{blue}{FOSSEE} team, which is funded by the
+ \end{center}
+ \begin{center}
+ \textcolor{blue}{National Mission on Education through \\
+ Information \& Communication Technology \\
+ MHRD, Govt. of India}.
+ \end{center}
+ \end{block}
+#+end_latex
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/getting-started-with-functions/slides.tex Wed Nov 10 18:58:11 2010 +0530
@@ -0,0 +1,323 @@
+% Created 2010-11-10 Wed 18:55
+\documentclass[presentation]{beamer}
+\usepackage[latin1]{inputenc}
+\usepackage[T1]{fontenc}
+\usepackage{fixltx2e}
+\usepackage{graphicx}
+\usepackage{longtable}
+\usepackage{float}
+\usepackage{wrapfig}
+\usepackage{soul}
+\usepackage{t1enc}
+\usepackage{textcomp}
+\usepackage{marvosym}
+\usepackage{wasysym}
+\usepackage{latexsym}
+\usepackage{amssymb}
+\usepackage{hyperref}
+\tolerance=1000
+\usepackage[english]{babel} \usepackage{ae,aecompl}
+\usepackage{mathpazo,courier,euler} \usepackage[scaled=.95]{helvet}
+\usepackage{listings}
+\lstset{language=Python, basicstyle=\ttfamily\bfseries,
+commentstyle=\color{red}\itshape, stringstyle=\color{darkgreen},
+showstringspaces=false, keywordstyle=\color{blue}\bfseries}
+\providecommand{\alert}[1]{\textbf{#1}}
+
+\title{Getting started with functions}
+\author{FOSSEE}
+\date{}
+
+\usetheme{Warsaw}\usecolortheme{default}\useoutertheme{infolines}\setbeamercovered{transparent}
+\begin{document}
+
+\maketitle
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+\begin{frame}
+\frametitle{Outline}
+\label{sec-1}
+
+\begin{itemize}
+\item Define functions
+\item Pass arguments to functions
+\item Learn about docstrings
+\item Return values from functions
+\end{itemize}
+\end{frame}
+\begin{frame}
+\frametitle{Function}
+\label{sec-2}
+
+\begin{itemize}
+\item Eliminate code redundancy
+\item Help in code reuse
+\item Subroutine
+
+\begin{itemize}
+\item relatively independent of remaining code
+\end{itemize}
+
+\end{itemize}
+\end{frame}
+\begin{frame}[fragile]
+\frametitle{\texttt{f(x)} a mathematical function}
+\label{sec-3}
+
+
+ $f(x) = x^{2}$
+
+\begin{verbatim}
+ f(1) -> 1
+ f(2) -> 4
+\end{verbatim}
+\end{frame}
+\begin{frame}[fragile]
+\frametitle{Define \texttt{f(x)} in Python}
+\label{sec-4}
+
+\begin{verbatim}
+def f(x):
+ return x*x
+\end{verbatim}
+
+\begin{itemize}
+\item \texttt{def} - keyword
+\item \texttt{f} - function name
+\item \texttt{x} - parameter / argument to function \texttt{f}
+\end{itemize}
+\end{frame}
+\begin{frame}
+\frametitle{Exercise 1}
+\label{sec-5}
+
+
+ Write a python function named \texttt{cube} which computes the cube of a given
+ number \texttt{n}.
+
+\begin{itemize}
+\item Pause here and try to solve the problem yourself.
+\end{itemize}
+\end{frame}
+\begin{frame}[fragile]
+\frametitle{Solution}
+\label{sec-6}
+
+\begin{verbatim}
+def cube(n):
+ return n**3
+\end{verbatim}
+\end{frame}
+\begin{frame}[fragile]
+\frametitle{\texttt{greet} function}
+\label{sec-7}
+
+
+ Function \texttt{greet} which will print \texttt{Hello World!}.
+\begin{verbatim}
+def greet():
+ print "Hello World!"
+\end{verbatim}
+\begin{itemize}
+\item Call the function \texttt{greet}
+\begin{verbatim}
+ In []: greet()
+ Hello World!
+\end{verbatim}
+
+\end{itemize}
+\end{frame}
+\begin{frame}
+\frametitle{Exercise 2}
+\label{sec-8}
+
+
+ Write a python function named \texttt{avg} which computes the average of
+ \texttt{a} and \texttt{b}.
+
+\begin{itemize}
+\item Pause here and try to solve the problem yourself.
+\end{itemize}
+\end{frame}
+\begin{frame}[fragile]
+\frametitle{Solution 2}
+\label{sec-9}
+
+\begin{verbatim}
+def avg(a,b):
+ return (a + b)/2
+\end{verbatim}
+
+\begin{itemize}
+\item \texttt{a} and \texttt{b} are parameters
+\item \texttt{def f(p1, p2, p3, ... , pn)}
+\end{itemize}
+\end{frame}
+\begin{frame}[fragile]
+\frametitle{Docstring}
+\label{sec-10}
+
+
+\begin{itemize}
+\item Documenting/commenting code is a good practice
+\begin{verbatim}
+def avg(a,b):
+ """ avg takes two numbers as input
+ (a & b), and returns the average
+ of a and b"""
+ return (a+b)/2
+\end{verbatim}
+\item Docstring
+
+\begin{itemize}
+\item written in the line after the \texttt{def} line.
+\item Inside triple quote.
+\end{itemize}
+
+\item Documentation
+\begin{verbatim}
+ avg?
+\end{verbatim}
+
+\end{itemize}
+\end{frame}
+\begin{frame}
+\frametitle{Exercise 3}
+\label{sec-11}
+
+ Add docstring to the function f.
+\end{frame}
+\begin{frame}[fragile]
+\frametitle{Solution 3}
+\label{sec-12}
+
+
+\begin{verbatim}
+def f(x):
+ """Accepts a number x as argument and,
+ returns the square of the number x."""
+ return x*x
+\end{verbatim}
+\end{frame}
+\begin{frame}
+\frametitle{Exercise 4}
+\label{sec-13}
+
+ Write a python function named \texttt{circle} which returns the area and
+ perimeter of a circle given radius \texttt{r}.
+\end{frame}
+\begin{frame}[fragile]
+\frametitle{Solution 4}
+\label{sec-14}
+
+\begin{verbatim}
+def circle(r):
+ """returns area and perimeter of a circle given
+ radius r"""
+ pi = 3.14
+ area = pi * r * r
+ perimeter = 2 * pi * r
+ return area, perimeter
+\end{verbatim}
+\end{frame}
+\begin{frame}[fragile]
+\frametitle{\texttt{what}}
+\label{sec-15}
+
+\begin{verbatim}
+
+def what( n ):
+ if n < 0: n = -n
+ while n > 0:
+ if n % 2 == 1:
+ return False
+ n /= 10
+ return True
+\end{verbatim}
+\end{frame}
+\begin{frame}[fragile]
+\frametitle{\texttt{even\_digits}}
+\label{sec-16}
+
+\begin{verbatim}
+def even_digits( n ):
+ """returns True if all the digits of number
+ n is even returns False if all the digits
+ of number n is not even"""
+ if n < 0: n = -n
+ while n > 0:
+ if n % 2 == 1:
+ return False
+ n /= 10
+ return True
+\end{verbatim}
+\end{frame}
+\begin{frame}[fragile]
+\frametitle{\texttt{what}}
+\label{sec-17}
+
+\begin{verbatim}
+def what( n ):
+ i = 1
+ while i * i < n:
+ i += 1
+ return i * i == n, i
+\end{verbatim}
+\end{frame}
+\begin{frame}[fragile]
+\frametitle{\texttt{is\_perfect\_square}}
+\label{sec-18}
+
+\begin{verbatim}
+def is_perfect_square( n ):
+ """returns True and square root of n,
+ if n is a perfect square, otherwise
+ returns False and the square root
+ of the next perfect square"""
+ i = 1
+ while i * i < n:
+ i += 1
+ return i * i == n, i
+\end{verbatim}
+\end{frame}
+\begin{frame}
+\frametitle{Summary}
+\label{sec-19}
+
+\begin{itemize}
+\item Functions in Python
+\item Passing parameters to a function
+\item Returning values from a function
+\item We also did few code reading exercises.
+\end{itemize}
+\end{frame}
+\begin{frame}
+\frametitle{Thank you!}
+\label{sec-20}
+
+ \begin{block}{}
+ \begin{center}
+ This spoken tutorial has been produced by the
+ \textcolor{blue}{FOSSEE} team, which is funded by the
+ \end{center}
+ \begin{center}
+ \textcolor{blue}{National Mission on Education through \\
+ Information \& Communication Technology \\
+ MHRD, Govt. of India}.
+ \end{center}
+ \end{block}
+\end{frame}
+
+\end{document}