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Diffstat (limited to 'getting-started-with-for')
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| -rw-r--r-- | getting-started-with-for/script.rst | 308 | ||||
| -rw-r--r-- | getting-started-with-for/slides.org | 146 | ||||
| -rw-r--r-- | getting-started-with-for/slides.tex | 285 |
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diff --git a/getting-started-with-for/quickref.tex b/getting-started-with-for/quickref.tex deleted file mode 100644 index d106d6d..0000000 --- a/getting-started-with-for/quickref.tex +++ /dev/null @@ -1,6 +0,0 @@ -For loop:\\ -{\ex \lstinline| for i in range(1,11,2):|} -{\ex \lstinline| s = s + i|} - -Range function:\\ -{\ex \lstinline| range([start,]stop[,step])|} diff --git a/getting-started-with-for/script.rst b/getting-started-with-for/script.rst deleted file mode 100644 index 69f925b..0000000 --- a/getting-started-with-for/script.rst +++ /dev/null @@ -1,308 +0,0 @@ -.. Objectives -.. ---------- - -.. At the end of this tutorial, you will be able to - -.. 1. Write blocks of code in python. -.. #. Use for loop. -.. #. Use ``range()`` function. -.. #. Write blocks in python interpreter -.. #. Write blocks in ipython interpreter. - - -.. Prerequisites -.. ------------- - -.. 1. should have ``ipython`` and ``pylab`` installed. -.. #. getting started with ``ipython``. -.. #. getting started with lists. - - -.. Author : Anoop Jacob Thomas <anoop@fossee.in> - Internal Reviewer : Nishanth - Internal Reviewer(2): Amit - External Reviewer : - Language Reviewer : Bhanukiran - Checklist OK? : <10-11-2010, Anand, OK> [2010-10-05] - - -============================= -Getting started with for loop -============================= - -{{{ show welcome slide }}} - -Hello and welcome to the tutorial `Getting started with ``for`` loop`. - -{{{ switch to next slide, outline slide }}} - -In this tutorial we will learn about ``for`` loops in python, and also -learn how to write blocks of code in Python. - -.. #[Nishanth]: Instead of saying basics of indenting code, - say How to define code blocks in Python - -{{{ switch to next slide, about whitespaces }}} - -In Python whitespace is significant, and the blocks are visually -separated. - -.. #[nishanth]: Simply tell how blocks are defined in python. - The details like braces are not used and its - advantages like neat code can be told after completely - explaining the indentation - -.. #[Amit]: Do you want to do that here. May be its better to talk about - this after some initiation into the idea of blocks. - -The best practice is to indent the code using four spaces. - -.. #[Nishanth]: Even this detail may be skipped. Simply say use 4 spaces - for indentation. Do that while typing so that they can - actually see what is being typed. - -As you can see in the slide, ``Block B`` is an inner block and it is -indented using 4 spaces, and after ``Block B`` the next statement in -``Block A`` starts from the same indentation level of other ``Block -A`` statements. - -Now let us move straight into ``for`` loop. - -{{{ switch to next slide, problem statement of exercise 1 }}} - - -Write a for loop which iterates through a list of numbers and find the -square root of each number. -:: - - numbers are 1369, 7225, 3364, 7056, 5625, 729, 7056, 576, 2916 - -.. #[nishanth]: making new list with square roots induces extra complication - like appending which has no use case here - -.. #[Nishanth]: The problem focuses more on square root and creation - of list. The problem must be simple and focusing on - nothing more but the indentation and for loop. - May be change the problem to print squares than to - print square roots. - -For the problem, first we need to create a ``list`` of numbers and -then iterate over the list and find the square root of each element in -it. And let us create a script, rather than typing it out in the -interpreter itself. Create a script called list_roots.py and type the -following. - -{{{ open the text editor and paste the following code there }}} -:: - - numbers = [1369, 7225, 3364, 7056, 5625, 729, 7056, 576, 2916] - for each in numbers: - print "Square root of", each, "is", sqrt(each) - print "This is not in for loop!" - -.. numbers = [1, 12, 3, 4, 21, 17] - for each in numbers: - print each, each * each - -.. #[nishanth]: I don't see a use case to append the sq_root to - square_roots. It is only complicating stuff. - Simply iterate and print. - -{{{ switch to next slide, save and run script }}} - -{{{ save the script }}} - -Now save the script, and run it from your IPython interpreter. I -assume that you have started your IPython interpreter using ``-pylab`` -option. - -Run the script as, -:: - - %run -i list_roots.py - -.. #[Nishanth]: you don't have to use the -i option here - -{{{ run the script }}} - -So that was easy! All what we did was iterate over the list element by -element and then use the element for calculation. Note that here we -used two variables. One the variable ``numbers``, which is a list, -another one ``each``, which is the element of list under consideration -in each cycle of the ``for`` loop. The variable names can be chosen by -you. - -.. #[Nishanth]: The details like we didn't have to find the length - are relevant for people who have programmed in C or - other languages earlier. But for a newbie it is more - of confusing extra info. That part may be skipped. - Simply go ahead and focus on the syntax of for loop. - And how the variable name is used inside the for loop. - If you modify the question to only print, the extra - variable sq_root can also be avoided. let it be more - about "each", "numbers" and "for". no other new names. - -{{{ show the script which was created }}} - -Note that the lines after ``for`` statement, is indented using four -spaces. - -{{{ highlight the line after for statement }}} - -It means that line is part of the for loop. And it is a block of code, -although it is only a single statement in the block. And the fourth -line or the immediate line after the ``for`` block is not indented, - -{{{ highlight the fourth line - the line just after for loop }}} - -it means that it is not part of the ``for`` loop and the lines after -that doesn't fall in the scope of the ``for`` loop. Thus each block is -separated by the indentation level and that marks the importance of -white-spaces in Python. - -{{{ switch to the slide which shows the problem statement of the first -problem to be tried out }}} - -Now a question for you to try, from the given numbers make a list of -perfect squares and a list of those which are not. The numbers are, -:: - - 7225, 3268, 3364, 2966, 7056, 5625, 729, 5547, 7056, 576, 2916 - -Pause here and try to solve the problem before proceeding further. - -{{{ switch to next slide, problem statement of second problem in -solved exercise}}} - -Now let us try a simple one, to print the square root of numbers in -the list. And this time let us do it right in the IPython -interpreter. - -{{{ switch to next slide, Indentation in ``ipython`` }}} - -{{{ switch focus to the IPython interpreter }}} - -So let us start with making a list. Type the following -:: - - numbers = [1369, 7225, 3364, 7056, 5625, 729, 7056, 576, 2916] - for each in numbers: - -and now you will notice that, as soon as you press the return key -after for statement, the prompt changes to four dots and the cursor is -not right after the four dots but there are four spaces from the -dots. Please note that IPython automatically indents the block. The -four dots tell you that you are inside a block. Now type the rest of -the ``for`` loop, - -{{{ switch to next slide, Indentation in ``ipython`` (cont'd) }}} - -.. #[Nishanth]: Tell that IPython does auto indentation. - -:: - - print "Square root of", each, - print "is", sqrt(each) - -Now we have finished the statements in the block, and still the -interpreter is showing four dots, this means that you are still inside the -block. To exit from the block press the return key or the enter key twice -without entering anything else. It printed the square root of each -number in the list, and that is executed in a ``for`` loop. - -{{{ switch to next slide, Indentation in ``python`` interpreter }}} - -Now, let us find the cube of all the numbers from one to ten. But this -time let us try it in the vanilla version of Python interpreter. - -Start the vanilla version of Python interpreter by issuing the command -``python`` in your terminal. - -{{{ open the python interpreter in the terminal using the command -python to start the vanilla Python interpreter }}} - -{{{ switch to next slide, Indentation in ``python`` interpreter -(cont'd) }}} - -Start with, -:: - - for i in range(1,11): - -and press enter once, and we will see that this time it shows four -dots, but the cursor is close to the dots, so we have to indent the -block. The vanilla version of Python interpreter does not indent the -code automatically. So enter four spaces there and then type the -following -:: - - print i, "cube is", i**3 - -Now when we hit enter, we still see the four dots, to get out of the -block, hit enter once again - -.. #[Nishanth]: Here also the overhead on print can be reduced. - Think of a simple print statement. This statement - will be confusing for a newbie. - We can focus more on indentation in python. - -.. #[nishanth]: Not sure if you must use range here. You can - define a list of numbers and iterate on it. - Then say this list can also be generated using - the range function and hence introduce range. - -{{{ switch to the next slide, ``range()`` function }}} - -Okay! so the main thing that we learned here is how to use Python -interpreter and IPython interpreter to specify blocks. But while we -were generating the multiplication table we used something new, -``range()`` function. ``range()`` is an inbuilt function in Python -which can be used to generate a ``list`` of integers from a starting -number to an ending number. Note that the ending number that you -specify will not be included in the ``list``. - -.. #[Nishanth]: Show some examples of range without the step argument - May be give an exercise with negative numbers as arguments - -{{{ switch to next slide, problem statement of the next problem in -solved exercises }}} - -Now, let us print all the odd numbers from 1 to 50. Pause here and try -to solve the problem yourself. - -Let us do it in our IPython interpreter for ease of use. - -{{{ switch focus to ipython interpreter }}} - -The problem can be solved by just using the ``range()`` function. - -It can be solved as, -:: - - print range(1,51,2) - -This time we passed three parameters to ``range()`` function unlike -the previous case where we passed only two parameters. The first two -parameters are the same in both the cases. The first parameter is the -starting number of the sequence and the second parameter is the end of -the range. Note that the sequence doesn't include the ending -number. The third parameter is for stepping through the sequence. Here -we gave two which means we are skipping every alternate element. - -{{{ switch to next slide, summary slide }}} - -Thus we come to the end of this tutorial. We learned about blocks in -Python, indentation, blocks in IPython, for loop, iterating over a -list and then the ``range()`` function. - -.. #[Amit]: There does seem to too much overhead of details. Should - the first example be done using script is it necessary. - Do add some things in evolutionary manner. Like introducing - range as a list and doing a very very simple for loop.Like - iterating over [1,2,3] .Before getting into a problem. - And club details about problem in one paragraph and syntactic details - in other. - -{{{ switch to next slide, thank you slide }}} - -Thank you! diff --git a/getting-started-with-for/slides.org b/getting-started-with-for/slides.org deleted file mode 100644 index 51cb7ab..0000000 --- a/getting-started-with-for/slides.org +++ /dev/null @@ -1,146 +0,0 @@ -#+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 for -#+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 - -* Outline - - ~for~ loop in Python. - - Blocks of code in Python. - - Indentation -* Whitespace in Python - - Whitespace is significant - - blocks are visually separated - - Blocks are indented using 4 spaces - : Block A - : Block A - : Block B - : Block B - : Block A - ~Block B~ is an inner block and is indented using 4 spaces -* Exercise 1 - Write a ~for~ loop which iterates through a list of numbers and find - the square root of each number. - : - The numbers are, - : 1369, 7225, 3364, 7056, 5625, 729, 7056, - : 576, 2916 -* Solution 1 - - Open text editor and type the following code - #+begin_src python - numbers = [1369, 7225, 3364, 7056, 5625, 729, 7056, - 576, 2916] - - for each in numbers: - print "Square root of", each, "is", sqrt(each) - - print "This is not in for loop!" - #+end_src -* Save \& run script - - Save the script as ~list_roots.py~ - - Run in ~ipython~ interpreter as, - : In []: %run -i list_roots.py -* Exercise 2 - From the given numbers make a list of perfect squares and a list of those which are not. - : - The numbers are, - : 7225, 3268, 3364, 2966, 7056, 5625, 729, 5547, - : 7056, 576, 2916 -* Exercise 3 (indentation in ~ipython~) - Print the square root of numbers in the list. - : - Numbers are, - : 7225, 3268, 3364, 2966, 7056, 5625, 729, 5547, - : 7056, 576, 2916 -* Indentation in ~ipython~ - : In []: numbers = [1369, 7225, 3364, 7056, 5625, - : ...: 729, 7056, 576, 2916] - - : In []: for each in numbers: - : ...: - Note the four spaces here - : - : - : - : - : - : -* Indentation in ~ipython~ (cont'd) - : In []: numbers = [1369, 7225, 3364, 7056, 5625, - : ...: 729, 7056, 576, 2916] - : In []: for each in numbers: - : ...: - Note the four spaces here - : - Now type the rest of the code - : ...: print "Square root of", each, - : ...: print "is", sqrt(each) - : ...: - : ...: -* Indentation in ~python~ interpreter - Find out the cube of all the numbers from 1 to 10. - : - /do it in the python interpreter/ -* Indentation in ~python~ interpreter (cont'd) - #+begin_src python - >>> for i in range(1, 11): - ... print i, "cube is", i**3 - ... - #+end_src -* ~range()~ function - - in built function in Python - - generates a list of integers - - /syntax:/ range([start,] stop[, step]) - - /example:/ - - range(1, 20) - /generates integers from 1 to 20/ - - range(20) - /generates integers from 0 to 20/ -* Exercise 4 - Print all the odd numbers from 1 to 50. -* Summary - - blocks in ~python~ - - indentation - - blocks in ~ipython~ interpreter - - ~for~ loop - - iterating over list using ~for~ loop - - ~range()~ function -* 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 - - diff --git a/getting-started-with-for/slides.tex b/getting-started-with-for/slides.tex deleted file mode 100644 index f6c1eaa..0000000 --- a/getting-started-with-for/slides.tex +++ /dev/null @@ -1,285 +0,0 @@ -% Created 2010-10-12 Tue 12:55 -\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 for} -\author{FOSSEE} -\date{} - -\usetheme{Warsaw}\usecolortheme{default}\useoutertheme{infolines}\setbeamercovered{transparent} -\begin{document} - -\maketitle - - - - - - - - - -\begin{frame} -\frametitle{Outline} -\label{sec-1} - -\begin{itemize} -\item \texttt{for} loop in Python. -\item Blocks of code in Python. - -\begin{itemize} -\item Indentation -\end{itemize} - -\end{itemize} -\end{frame} -\begin{frame}[fragile] -\frametitle{Whitespace in Python} -\label{sec-2} - -\begin{itemize} -\item Whitespace is significant - -\begin{itemize} -\item blocks are visually separated -\end{itemize} - -\item Blocks are indented using 4 spaces -\begin{verbatim} - Block A - Block A - Block B - Block B - Block A -\end{verbatim} - - \texttt{Block B} is an inner block and is indented using 4 spaces -\end{itemize} -\end{frame} -\begin{frame}[fragile] -\frametitle{Exercise 1} -\label{sec-3} - - Write a \texttt{for} loop which iterates through a list of numbers and find - the square root of each number. -\begin{verbatim} - -\end{verbatim} - - The numbers are, -\begin{verbatim} - 1369, 7225, 3364, 7056, 5625, 729, 7056, - 576, 2916 -\end{verbatim} -\end{frame} -\begin{frame}[fragile] -\frametitle{Solution 1} -\label{sec-4} - -\begin{itemize} -\item Open text editor and type the following code -\end{itemize} - -\begin{verbatim} -numbers = [1369, 7225, 3364, 7056, 5625, 729, 7056, - 576, 2916] - -for each in numbers: - print "Square root of", each, "is", sqrt(each) - -print "This is not in for loop!" -\end{verbatim} -\end{frame} -\begin{frame}[fragile] -\frametitle{Save \& run script} -\label{sec-5} - -\begin{itemize} -\item Save the script as \texttt{list\_roots.py} -\item Run in \texttt{ipython} interpreter as, -\begin{verbatim} - In []: %run -i list_roots.py -\end{verbatim} - -\end{itemize} -\end{frame} -\begin{frame}[fragile] -\frametitle{Exercise 2} -\label{sec-6} - - From the given numbers make a list of perfect squares and a list of those which are not. -\begin{verbatim} - -\end{verbatim} - - The numbers are, -\begin{verbatim} - 7225, 3268, 3364, 2966, 7056, 5625, 729, 5547, - 7056, 576, 2916 -\end{verbatim} -\end{frame} -\begin{frame}[fragile] -\frametitle{Exercise 3 (indentation in \texttt{ipython})} -\label{sec-7} - - Print the square root of numbers in the list. -\begin{verbatim} - -\end{verbatim} - - Numbers are, -\begin{verbatim} - 7225, 3268, 3364, 2966, 7056, 5625, 729, 5547, - 7056, 576, 2916 -\end{verbatim} -\end{frame} -\begin{frame}[fragile] -\frametitle{Indentation in \texttt{ipython}} -\label{sec-8} - -\begin{verbatim} - In []: numbers = [1369, 7225, 3364, 7056, 5625, - ...: 729, 7056, 576, 2916] -\end{verbatim} - - -\begin{verbatim} - In []: for each in numbers: - ...: -\end{verbatim} - - Note the four spaces here -\begin{verbatim} - - - - - - -\end{verbatim} -\end{frame} -\begin{frame}[fragile] -\frametitle{Indentation in \texttt{ipython} (cont'd)} -\label{sec-9} - -\begin{verbatim} - In []: numbers = [1369, 7225, 3364, 7056, 5625, - ...: 729, 7056, 576, 2916] - In []: for each in numbers: - ...: -\end{verbatim} - - Note the four spaces here -\begin{verbatim} - -\end{verbatim} - - Now type the rest of the code -\begin{verbatim} - ...: print "Square root of", each, - ...: print "is", sqrt(each) - ...: - ...: -\end{verbatim} -\end{frame} -\begin{frame}[fragile] -\frametitle{Indentation in \texttt{python} interpreter} -\label{sec-10} - - Find out the cube of all the numbers from 1 to 10. -\begin{verbatim} - -\end{verbatim} - - \emph{do it in the python interpreter} -\end{frame} -\begin{frame}[fragile] -\frametitle{Indentation in \texttt{python} interpreter (cont'd)} -\label{sec-11} - -\begin{verbatim} ->>> for i in range(1, 11): -... print i, "cube is", i**3 -... -\end{verbatim} -\end{frame} -\begin{frame} -\frametitle{\texttt{range()} function} -\label{sec-12} - -\begin{itemize} -\item in built function in Python -\item generates a list of integers - -\begin{itemize} -\item \emph{syntax:} range([start,] stop[, step]) -\item \emph{example:} - -\begin{itemize} -\item range(1, 20) - \emph{generates integers from 1 to 20} -\item range(20) - \emph{generates integers from 0 to 20} -\end{itemize} - -\end{itemize} - -\end{itemize} -\end{frame} -\begin{frame} -\frametitle{Exercise 4} -\label{sec-13} - - Print all the odd numbers from 1 to 50. -\end{frame} -\begin{frame} -\frametitle{Summary} -\label{sec-14} - -\begin{itemize} -\item blocks in \texttt{python} -\item indentation -\item blocks in \texttt{ipython} interpreter -\item \texttt{for} loop -\item iterating over list using \texttt{for} loop -\item \texttt{range()} function -\end{itemize} -\end{frame} -\begin{frame} -\frametitle{Thank you!} -\label{sec-15} - - \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} |