diff options
Diffstat (limited to 'embellishing_a_plot')
| -rw-r--r-- | embellishing_a_plot/quickref.tex | 11 | ||||
| -rw-r--r-- | embellishing_a_plot/script.rst | 371 | ||||
| -rw-r--r-- | embellishing_a_plot/slides.tex | 106 |
3 files changed, 488 insertions, 0 deletions
diff --git a/embellishing_a_plot/quickref.tex b/embellishing_a_plot/quickref.tex new file mode 100644 index 0000000..a0212b3 --- /dev/null +++ b/embellishing_a_plot/quickref.tex @@ -0,0 +1,11 @@ +Creating a tuple:\\ +{\ex \lstinline| t = (1, "hello", 2.5)|} + +Accessing elements of tuples:\\ +{\ex \lstinline| t[index] Ex: t[2]|} + +Accessing slices of tuples:\\ +{\ex \lstinline| t[start:stop:step]|} + +Swapping values:\\ +{\ex \lstinline| a, b = b, a|} diff --git a/embellishing_a_plot/script.rst b/embellishing_a_plot/script.rst new file mode 100644 index 0000000..b37365b --- /dev/null +++ b/embellishing_a_plot/script.rst @@ -0,0 +1,371 @@ +.. Objectives +.. ---------- + +.. A - Students and teachers from Science and engineering backgrounds + B - + C - + D - + +.. Prerequisites +.. ------------- + +.. 1. Using the ``plot`` command interactively + +.. Author : Nishanth Amuluru + Internal Reviewer : + External Reviewer : + Checklist OK? : <put date stamp here, if OK> [2010-10-05] + +Script +------ + +Hello friends and welcome to the tutorial on Embellishing Plots. + +{{{ Show the slide containing title }}} + +{{{ Show the slide containing the outline }}} + +In this tutorial, we shall look at how to modify the colour, thickness and +linestyle of the plot. We shall then learn how to add title to the plot and +then look at adding labels to x and y axes. we shall also look at adding +annotations to the plot and setting the limits of axes. + +Let us start ipython with pylab loaded, by typing on the terminal + +{{{ shift to terminal and type ipython -pylab }}} + +:: + + ipython -pylab + +.. #[madhu: I feel the instructions should precede the actual action, + +since while recording we need to know before hand what we need to do] + +We shall first make a simple plot and start decorating it. + +.. #[madhu: start decorating it should be fine, with is not necessary] + +:: + + x = linspace(-2, 4, 20) + plot(x, sin(x)) + +.. #[madhu: Standard is to choose between -50 to 50 or 0 to 50 with 100 + points right?] + +As we can see, the default colour and the default thickness of the +line is as decided by pylab. Wouldn't be nice if we could control +these parameters in the plot? This is possible by passing additional +arguments to the plot command. + +.. #[[Anoop: I think it will be good to rephrase the sentence]] +.. #[madhu: Why "you" here? Shouldn't this be "we" as decided? Also I + added "the default" check the diff] + +The additional argument that we shall be passing in here now is the +colour argument. We shall first clear the figure and plot the same in +red colour. Hence + +.. #[Madhu: Note the diff for changes] + :: + + clf() + plot(x, sin(x), 'r') + +As we can see we have the same plot but now in red colour. + +.. #[Madhu: diff again] + +To alter the thickness of the line, we use the ``linewidth`` argument in the plot +command. Hence +:: + + plot(x, cos(x), linewidth=2) + +produces a plot with a thicker line, to be more precise plot with line +thickness 2. + +.. #[[Anoop: I guess it will be good if you say that it affects the + same plot, as you have not cleared the figure]] +.. #[Madhu: To Anoop, not necessary I feel since they can see it?] + +{{{ Show the plot and compare the sine and cos plots }}} + +{{{ Pause here and try out the following exercises }}} + +.. #[[Anoop: is the above a context switch for the person who does the + recording, other wise if it an instruction to the person viewing + the video, then I guess the three braces can be removed.]] + +%% 1 %% Plot sin(x) in blue colour and with linewidth as 3 + +{{{ continue from paused state }}} + +A combination of colour and linewidth would do the job for us. Hence +:: + + clf() + plot(x, sin(x), 'b', linewidth=3) + +.. #[[Anoop: add clf()]] + +produces the required plot + +.. #[Nishanth]: I could not think of a SIMPLE recipe approach for + introducing linestyle. Hence the naive approach. + +.. #[[Anoop: I guess the recipe is fine, but would be better if you + add the problem statement rather than just saying "let's do a simple + plot"]] + +.. #[Madhu: It is good enough.] + +Occasionally we would also want to alter the style of line. Sometimes +all we want is just a bunch of points not joined. This is possible by +passing the linestyle argument along with or instead of the colour +argument. Hence :: + + clf() + plot(x, sin(x), '.') + +produces a plot with only points. + +To produce the same plot but now in blue colour, we do +:: + + clf() + plot(x, sin(x), 'b.') + +Other available options can be seen in the documentation of plot. +:: + + plot? + +{{{ Run through the documentation and show the options available }}} + +{{{ Show the options available for line style and colors }}} + +.. #[Madhu: The script needs to tell what needs to be shown or + explained.] + +{{{ Pause here and try out the following exercises }}} + +.. #[[Anoop: same question as above, should it be read out?]] + +%% 2 %% Plot the sine curve with green filled circles. + +{{{ continue from paused state }}} + +All we have to do is use a combination of linestyle and colour to acheive this. +Hence +:: + + clf() + plot(x, cos(x), 'go') + +produces the required plot. + +{{{ Pause here and try out the following exercises }}} + +%% 3 %% Plot the curve of x vs tan(x) in red dashed line and linewidth 3 + +{{{ continue from paused state }}} + +.. #[Madhu: I did not understand the question] + +Now that we know how to produce a bare minimum plot with colour, style +and thickness of our interest, we shall look at decorating the plot. + +Let us start with a plot of the function -x^2 + 4x - 5. +:: + + plot(x, -x*x + 4*x - 5, 'r', linewidth=2) + +{{{ Show the plot window and switch back to terminal }}} + +We now have the plot in a colour and linewidth of our interest. As you can see, +the figure does not have any description describing the plot. + +.. #[Madhu: Added "not". See the diff] + +We will now add a title to the plot by using the ``title`` command. +:: + + title("Parabolic function -x^2+4x-5") + +{{{ Show the plot window and point to the title }}} + +The figure now has a title which describes what the plot is. The +``title`` command as you can see, takes a string as an argument and sets +the title accordingly. + +.. #[Madhu: See the diff] + +The formatting in title is messed and it does not look clean. You can imagine +what would be the situation if there were fractions and more complex functions +like log and exp. Wouldn't it be good if there was LaTex like formatting? + +That is also possible by adding a $ sign before and after the part of the +string that should be in LaTex style. + +for instance, we can use +:: + + title("Parabolic function $-x^2+4x-5$") + +and we get the polynomial formatted properly. + +.. #[Nishanth]: Unsure if I have to give this exercise since enclosing the whole + string in LaTex style is not good + +.. #[[Anoop: I guess you can go ahead with the LaTex thing, it's + cool!]] +.. #[Madhu: Instead of saying LaTeX style you can say Typeset math + since that is how it is called as. I am not sure as well. It + doesn't really solve the purpose] + +{{{ Pause here and try out the following exercises }}} + +%% 4 %% Change the title of the figure such that the whole title is formatted + in LaTex style + +{{{ continue from the paused state }}} + +The solution is to enclose the whole string in between $. Hence, +:: + + title("$Parabolic function -x^2+4x-5$") + +gives a title that looks neatly formatted. + +Although we have title, the plot is not complete without labelling x +and y axes. Hence we shall label x-axis to "x" and y-axis to "f(x)" :: + + xlabel("x") + +{{{ Switch to plot window and show the xlabel }}} + +As you can see, ``xlabel`` command takes a string as an argument, +similar to the ``title`` command and sets it as the label to x-axis. + +.. #[See the diff] + +Similarly, +:: + + ylabel("f(x)") + +sets the name of the y-axis as "f(x)" + +{{{ Show the plot window and point to ylabel and switch back to the terminal }}} + +{{{ Pause here and try out the following exercises }}} + +%% 5 %% Set the x and y labels as "x" and "f(x)" in LaTex style. + +{{{ continue from paused state }}} + +Since we need LaTex style formatting, all we have to do is enclose the string +in between two $. Hence, +:: + + xlabel("$x$") + yalbel("$f(x)$") + +does the job for us. + +{{{ Show the plot window with clean labels }}} + +The plot is now almost complete. Except that we have still not seen how to +name the points. For example the point (2, -1) is the local maxima. We would +like to name the point accordingly. We can do this by using +:: + + annotate("local maxima", xy=(2, -1)) + +{{{ Show the annotation that has appeared on the plot }}} + +As you can see, the first argument to ``annotate`` command is the name we would +like to mark the point as and the second argument is the co-ordinates of the +point at which the name should appear. It is a sequence containing two numbers. +The first is x co-ordinate and second is y co-ordinate. + +.. #[[Anoop: I think we should tell explicitely that xy takes a + sequence or a tuple]] +.. #[Madhu: Agreed to what anoop says and also that xy= is the point + part should be rephrased I think.] + +{{{ Pause here and try out the following exercises }}} + +%% 6 %% Make an annotation called "root" at the point (-4, 0) + What happens to the first annotation ? + +{{{ continue from paused state }}} + +As we can see, every annotate command makes a new annotation on the figure. + +Now we have everything we need to decorate a plot. but the plot would be +incomplete if we can not set the limits of axes. This is possible using the +button on the plot window. + +we shall look at how to get and set them from the script. +:: + + xlim() + ylim() + +We see that ``xlim`` function returns the current x axis limits and ylim +function returns the current y-axis limits. + +Let us look at how to set the limits. +:: + + xlim(-4, 5) + +We see the limits of x-axis are now set to -4 and 5. +Similarly +:: + + ylim(-15, 2) + +sets the limits of y-axis appropriately. + +{{{ Pause here and try out the following exercises }}} + +%% 7 %% Set the limits of axes such that the area of interest is the rectangle + (-1, -15) and (3, 0) + +{{{ continue from paused state }}} + +As we can see, the lower upper limits of x-axis in the question are -1 and 3. +The limits of y-axis are -15 and 0. + +:: + + xlim(-1, 3) + ylim(-15, 0) + +Gives us the required rectangle. + +{{{ Show summary slide }}} + +we have looked at + + * Modifying the attributes of plot by passing additional arguments + * How to add title + * How to incorporate LaTex style formatting + * How to label x and y axes + * How to add annotations + * How to set the limits of axes + +{{{ Show the "sponsored by FOSSEE" slide }}} + +.. #[Nishanth]: Will add this line after all of us fix on one. + +This tutorial was created as a part of FOSSEE project, NME ICT, MHRD India + +Hope you have enjoyed and found it useful. +Thankyou + + diff --git a/embellishing_a_plot/slides.tex b/embellishing_a_plot/slides.tex new file mode 100644 index 0000000..df1462c --- /dev/null +++ b/embellishing_a_plot/slides.tex @@ -0,0 +1,106 @@ +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +%Tutorial slides on Python. +% +% Author: FOSSEE +% Copyright (c) 2009, FOSSEE, IIT Bombay +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +\documentclass[14pt,compress]{beamer} +%\documentclass[draft]{beamer} +%\documentclass[compress,handout]{beamer} +%\usepackage{pgfpages} +%\pgfpagesuselayout{2 on 1}[a4paper,border shrink=5mm] + +% Modified from: generic-ornate-15min-45min.de.tex +\mode<presentation> +{ + \usetheme{Warsaw} + \useoutertheme{infolines} + \setbeamercovered{transparent} +} + +\usepackage[english]{babel} +\usepackage[latin1]{inputenc} +%\usepackage{times} +\usepackage[T1]{fontenc} + +\usepackage{ae,aecompl} +\usepackage{mathpazo,courier,euler} +\usepackage[scaled=.95]{helvet} + +\definecolor{darkgreen}{rgb}{0,0.5,0} + +\usepackage{listings} +\lstset{language=Python, + basicstyle=\ttfamily\bfseries, + commentstyle=\color{red}\itshape, + stringstyle=\color{darkgreen}, + showstringspaces=false, + keywordstyle=\color{blue}\bfseries} + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +% Macros +\setbeamercolor{emphbar}{bg=blue!20, fg=black} +\newcommand{\emphbar}[1] +{\begin{beamercolorbox}[rounded=true]{emphbar} + {#1} + \end{beamercolorbox} +} +\newcounter{time} +\setcounter{time}{0} +\newcommand{\inctime}[1]{\addtocounter{time}{#1}{\tiny \thetime\ m}} + +\newcommand{\typ}[1]{\lstinline{#1}} + +\newcommand{\kwrd}[1]{ \texttt{\textbf{\color{blue}{#1}}} } + +% Title page +\title{Your Title Here} + +\author[FOSSEE] {FOSSEE} + +\institute[IIT Bombay] {Department of Aerospace Engineering\\IIT Bombay} +\date{} + +% DOCUMENT STARTS +\begin{document} + +\begin{frame} + \maketitle +\end{frame} + +\begin{frame}[fragile] + \frametitle{Outline} + \begin{itemize} + \item + \end{itemize} +\end{frame} + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +%% All other slides here. %% +%% The same slides will be used in a classroom setting. %% +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +\begin{frame}[fragile] + \frametitle{Summary} + \begin{itemize} + \item + \end{itemize} +\end{frame} + +\begin{frame} + \frametitle{Thank you!} + \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} |