1 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

     2 % Tutorial slides on Python.

     3 %

     4 % Author: Prabhu Ramachandran <prabhu at aero.iitb.ac.in>

     5 % Copyright (c) 2005-2009, Prabhu Ramachandran

     6 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

     7 

     8 \documentclass[compress,14pt]{beamer}

     9 % \documentclass[handout]{beamer}

    10 % \usepackage{pgfpages}

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    12 \usepackage{tikz}

    13 \newcommand{\hyperlinkmovie}{}

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    15 

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    17 % Note that in presentation mode 

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    20 % h/w = 0.888

    21 

    22 

    23 \mode<presentation>

    24 {

    25   \usetheme{Warsaw}

    26   %\usetheme{Boadilla}

    27   %\usetheme{default}

    28   \useoutertheme{split}

    29   \setbeamercovered{transparent}

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    31 

    32 % To remove navigation symbols

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    34 

    35 \usepackage{amsmath}

    36 \usepackage[english]{babel}

    37 \usepackage[latin1]{inputenc}

    38 \usepackage{times}

    39 \usepackage[T1]{fontenc}

    40 

    41 % Taken from Fernando's slides.

    42 \usepackage{ae,aecompl}

    43 \usepackage{mathpazo,courier,euler}

    44 \usepackage[scaled=.95]{helvet}

    45 \usepackage{pgf}

    46 

    47 \definecolor{darkgreen}{rgb}{0,0.5,0}

    48 

    49 \usepackage{listings}

    50 \lstset{language=Python,

    51     basicstyle=\ttfamily\bfseries,

    52     commentstyle=\color{red}\itshape,

    53   stringstyle=\color{darkgreen},

    54   showstringspaces=false,

    55   keywordstyle=\color{blue}\bfseries}

    56 

    57 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

    58 % My Macros

    59 \setbeamercolor{postit}{bg=yellow,fg=black}

    60 \setbeamercolor{emphbar}{bg=blue!20, fg=black}

    61 \newcommand{\emphbar}[1]

    62 {\begin{beamercolorbox}[rounded=true]{emphbar} 

    63       {#1}

    64  \end{beamercolorbox}

    65 }

    66 %{\centerline{\fcolorbox{gray!50} {blue!10}{

    67 %\begin{minipage}{0.9\linewidth}

    68 %    {#1} 

    69 %\end{minipage}

    70 %    }}}

    71 

    72 \newcommand{\myemph}[1]{\structure{\emph{#1}}}

    73 \newcommand{\PythonCode}[1]{\lstinline{#1}}

    74 

    75 \newcommand{\tvtk}{\texttt{tvtk}}

    76 \newcommand{\mlab}{\texttt{mlab}}

    77 

    78 \newcounter{time}

    79 \setcounter{time}{0}

    80 \newcommand{\inctime}[1]{\addtocounter{time}{#1}{\vspace*{0.1in}\tiny \thetime\ m}}

    81 

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    85       \vfill \hfill

    86  \hfill \vfill

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    88 

    89 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

    90 % Configuring the theme

    91 %\setbeamercolor{normal text}{fg=white}

    92 %\setbeamercolor{background canvas}{bg=black}

    93 

    94 

    95 

    96 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

    97 % Title page

    98 \title[]{3D data Visualization}

    99 

   100 \author[FOSSEE Team] {FOSSEE}

   101 

   102 \institute[IIT Bombay] {Department of Aerospace Engineering\\IIT Bombay}

   103 \date[] {1, November 2009\\Day 2, Session 3}

   104 

   105 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   106 

   107 %\pgfdeclareimage[height=0.75cm]{iitblogo}{iitblogo}

   108 %\logo{\pgfuseimage{iitblogo}}

   109 

   110 \AtBeginSection[]

   111 {

   112   \begin{frame}<beamer>

   113     \frametitle{Outline}      

   114     \tableofcontents[currentsection,currentsubsection]

   115   \end{frame}

   116 }

   117 

   118 %% Delete this, if you do not want the table of contents to pop up at

   119 %% the beginning of each subsection:

   120 \AtBeginSubsection[]

   121 {

   122   \begin{frame}<beamer>

   123     \frametitle{Outline}

   124     \tableofcontents[currentsection,currentsubsection]

   125   \end{frame}

   126 }

   127 

   128 \AtBeginSection[]

   129 {

   130   \begin{frame}<beamer>

   131     \frametitle{Outline}

   132     \tableofcontents[currentsection,currentsubsection]

   133   \end{frame}

   134 }

   135 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   136 % DOCUMENT STARTS

   137 \begin{document}

   138 

   139 \begin{frame}

   140   \maketitle

   141 \end{frame}

   142 

   143 \begin{frame}

   144   \frametitle{Outline}

   145   \tableofcontents

   146   % You might wish to add the option [pausesections]

   147 \end{frame}

   148 

   149 \section{3D Data Visualization}

   150 

   151 \begin{frame}

   152     \frametitle{What is visualization?}

   153     \Large

   154     \begin{center}

   155     Visual representation of data

   156     \end{center}

   157 \end{frame}

   158 

   159 

   160 \begin{frame}

   161     \frametitle{Is this new?}    

   162     \begin{center}

   163     We have moved from:

   164     \end{center}

   165     \begin{columns}

   166     \column{}

   167     \hspace*{-1in}    

   168     \includegraphics[width=1.75in,height=1.75in, interpolate=true]{data/3832}      

   169     \column{}\hspace*{-0.25in}

   170     To

   171     \column{}

   172     \hspace*{-1in}

   173     \includegraphics[width=1.75in, height=1.75in, interpolate=true]{data/torus}  

   174     \end{columns}

   175 \end{frame}

   176 

   177 \begin{frame}

   178     \frametitle{3D visualization}

   179     \Large

   180     \begin{center}

   181         Harder but important

   182     \end{center}

   183 \end{frame}

   184 

   185 \begin{frame}

   186     \frametitle{Is this Graphics?}

   187     \Large

   188     \begin{center}

   189         Visualization is about data!

   190     \end{center}

   191 \end{frame}

   192 

   193 \begin{frame}

   194     \frametitle{Examples: trajectory in space}

   195     \Large

   196     \begin{center}

   197         \pgfimage[width=2.5in]{MEDIA/m2/mlab/plot3d_ex}

   198     \end{center}

   199 \end{frame}

   200 

   201 \begin{frame}

   202     \frametitle{Examples: Fire in a room}

   203     \Large

   204     \begin{center}

   205         Demo of data

   206     \end{center}

   207 \inctime{10}

   208 \end{frame}

   209 

   210 \section{Tools available}

   211 

   212 \subsection{mlab}

   213 

   214 \begin{frame}

   215     {Overview}

   216     \Large

   217     \begin{itemize}

   218         \item Simple

   219         \item Convenient

   220         \item Full-featured

   221     \end{itemize}

   222 \end{frame}

   223 

   224 \begin{frame}[fragile]

   225 

   226     \frametitle{Getting started}

   227     \myemph{\Large Vanilla:}

   228     \begin{lstlisting}[language=bash]

   229         $ ipython -wthread

   230     \end{lstlisting}

   231     \myemph{\Large with Pylab:}

   232     \begin{lstlisting}[language=bash]

   233         $ ipython -pylab -wthread

   234     \end{lstlisting}

   235 \end{frame}

   236 

   237 \begin{frame}[fragile]

   238     \frametitle{Using mlab}

   239 

   240     \begin{lstlisting}

   241 >>> from enthought.mayavi import mlab

   242     \end{lstlisting}

   243 

   244     \vspace*{0.5in}

   245 

   246     \myemph{\Large Try these}

   247 

   248     \vspace*{0.25in}

   249 

   250     \begin{lstlisting}

   251 >>> mlab.test_<TAB>

   252 >>> mlab.test_contour3d()

   253 >>> mlab.test_contour3d??

   254     \end{lstlisting}

   255 \end{frame}

   256 

   257 \begin{frame}

   258     {Exploring the view}

   259     \begin{columns}

   260         \column{0.6\textwidth}

   261     \pgfimage[width=3in]{MEDIA/m2/contour3d}

   262         \column{0.4\textwidth}

   263         \begin{itemize}

   264             \item Mouse

   265             \item Keyboard

   266             \item Toolbar

   267             \item Mayavi icon\pgfimage[width=0.2in]{MEDIA/m2/m2_icon}

   268         \end{itemize}

   269     \end{columns}

   270 \end{frame}

   271 

   272 \begin{frame}[fragile]

   273     \frametitle{plotting 3-D Surface: $x^2+y^2-z^2=1$}

   274     \begin{lstlisting}

   275 u,v = mgrid[-2:2:100j, -pi:pi:100j]

   276 x=sqrt(u*u+1)*cos(v)

   277 y=sqrt(u*u+1)*sin(v)

   278 z=u

   279 mlab.mesh(x,y,z)

   280     \end{lstlisting}

   281 \begin{figure}

   282 \includegraphics[width=1in, height=1in, interpolate=true]{data/hyperboloid}

   283 \end{figure}

   284 \end{frame}

   285 

   286 \begin{frame}[fragile]

   287     \frametitle{mgrid}    

   288     \begin{itemize}

   289       \item Creates a multidimensional ``meshgrid''

   290       

   291       \item In this particular case, creates 2 2D arrays: u,v.

   292     \end{itemize}      

   293     \begin{lstlisting}

   294 In []: mgrid[0:3,0:3]

   295 Out[]: 

   296 array([[[0, 0, 0],

   297         [1, 1, 1],

   298         [2, 2, 2]],

   299 

   300        [[0, 1, 2],

   301         [0, 1, 2],

   302         [0, 1, 2]]])

   303     \end{lstlisting}    

   304 \end{frame}

   305 

   306 \begin{frame}[fragile]

   307     \frametitle{mesh}

   308       \begin{itemize}

   309         \item Plots a surface from data supplied as 2D arrays.

   310       \end{itemize}      

   311 \end{frame}

   312 

   313 \begin{frame}[fragile]

   314     \frametitle{\mlab\ plotting functions}

   315     \begin{columns}

   316         \column{0.25\textwidth}

   317         \myemph{Points in 3D space}

   318         \column{0.5\textwidth}

   319     \pgfimage[width=2in]{MEDIA/m2/mlab/points3d_ex}

   320     \end{columns}

   321 

   322     \begin{lstlisting}

   323 >>> from numpy import *

   324 >>> t = linspace(0, 2*pi, 50)

   325 >>> u = cos(t)*pi

   326 >>> x, y, z = sin(u), cos(u), sin(t)

   327     \end{lstlisting}

   328     \emphbar{\PythonCode{>>> mlab.points3d(x, y, z)}}

   329 \end{frame}

   330 

   331 \begin{frame}

   332   \begin{columns}

   333         \column{0.25\textwidth}

   334         \myemph{Connected points in 3D space}

   335         \column{0.5\textwidth}

   336         \pgfimage[width=2.5in]{MEDIA/m2/mlab/plot3d_ex}

   337   \end{columns}

   338   \emphbar{\PythonCode{>>> mlab.plot3d(x, y, z, t)}}

   339 

   340     Plots lines between the points

   341     

   342 \end{frame}

   343 

   344 \begin{frame}[fragile]

   345     \begin{columns}

   346         \column{0.25\textwidth}

   347         \myemph{\Large 2D data}

   348         \column{0.5\textwidth}

   349         \pgfimage[width=2in]{MEDIA/m2/mlab/surf_ex}

   350     \end{columns}            

   351     \begin{lstlisting}

   352 >>> x, y = mgrid[-3:3:100j,-3:3:100j]

   353 >>> z = sin(x*x + y*y)

   354     \end{lstlisting}

   355 

   356     \emphbar{\PythonCode{>>> mlab.surf(x, y, z)}}

   357 

   358     \alert{Assumes the points are rectilinear}

   359 

   360 \end{frame}

   361 

   362 \begin{frame}[fragile]

   363     \myemph{\Large 2D data: \texttt{mlab.mesh}}

   364     \vspace*{0.25in}

   365 

   366     \emphbar{\PythonCode{>>> mlab.mesh(x, y, z)}}

   367 

   368     \alert{Points needn't be regular}

   369 

   370     \vspace*{0.25in}

   371 \begin{lstlisting}

   372 >>> phi, theta = numpy.mgrid[0:pi:20j, 

   373 ...                         0:2*pi:20j]

   374 >>> x = sin(phi)*cos(theta)

   375 >>> y = sin(phi)*sin(theta)

   376 >>> z = cos(phi)

   377 >>> mlab.mesh(x, y, z, 

   378 ...           representation=

   379 ...           'wireframe')

   380 \end{lstlisting}

   381 

   382 \end{frame}

   383 

   384 \begin{frame}[fragile]

   385 

   386   \begin{columns}

   387         \column{0.25\textwidth}

   388         \myemph{\Large 3D data}

   389         \column{0.5\textwidth}

   390         \pgfimage[width=1.5in]{MEDIA/m2/mlab/contour3d}\\        

   391     \end{columns}

   392 \begin{lstlisting}

   393 >>> x, y, z = ogrid[-5:5:64j, 

   394 ...                -5:5:64j, 

   395 ...                -5:5:64j]

   396 >>> mlab.contour3d(x*x*0.5 + y*y + 

   397                    z*z*2)

   398 \end{lstlisting}

   399 \end{frame}

   400 

   401 \begin{frame}[fragile]

   402 

   403     \myemph{\Large 3D vector data: \PythonCode{mlab.quiver3d}}

   404     \vspace*{0.25in}

   405 

   406     \pgfimage[width=2in]{MEDIA/m2/mlab/quiver3d_ex}\\

   407     

   408 \begin{lstlisting}

   409 >>> mlab.test_quiver3d()

   410 \end{lstlisting}

   411 

   412 \emphbar{\PythonCode{obj = mlab.quiver3d(x, y, z, u, v, w)}}

   413 \inctime{20}

   414 \end{frame}

   415 

   416 

   417 \subsection{Mayavi2}

   418 

   419 \begin{frame}

   420   \frametitle{Introduction to Mayavi}

   421   \begin{itemize}

   422   \item Most scientists not interested in details of visualization

   423   \item Visualization of data files with a nice UI

   424   \item Interactive visualization of data (think Matlab)

   425   \item Embedding visualizations in applications

   426   \item Customization

   427   \end{itemize}

   428   \pause

   429   \begin{block}{The Goal}

   430       Provide a \alert{flexible} library/app for every one of these needs!

   431   \end{block}

   432 \end{frame}

   433 

   434 \begin{frame}

   435     {Overview of features}

   436       \vspace*{-0.3in}

   437   \begin{center}    

   438     \hspace*{-0.2in}\pgfimage[width=5in]{MEDIA/m2/m2_app3_3}

   439   \end{center}    

   440 \end{frame}

   441 

   442 

   443 \begin{frame}

   444     \frametitle{Mayavi in applications}

   445       \vspace*{-0.3in}

   446   \begin{center}    

   447     \hspace*{-0.2in}\pgfimage[width=4.5in]{MEDIA/m2/m2_envisage}

   448   \end{center}

   449 \end{frame}

   450 

   451 \begin{frame}

   452     \frametitle{Live in your dialogs}

   453       \vspace*{0.1in}

   454   \begin{center}    

   455     \hspace*{-0.2in}\pgfimage[width=2.5in]{MEDIA/m2/mlab_tui}

   456   \end{center}

   457 \end{frame}

   458 

   459 \begin{frame}

   460     {Exploring the documentation}

   461     \begin{center}

   462     \pgfimage[width=4in]{MEDIA/m2/m2_ug_doc}

   463     \end{center}

   464 \end{frame}

   465 

   466 

   467 \begin{frame}

   468   \frametitle{Summary}

   469       \begin{itemize}

   470           \item \url{http://code.enthought.com/projects/mayavi}

   471           \item Uses VTK (\url{www.vtk.org})

   472           \item BSD license

   473           \item Linux, win32 and Mac OS X

   474           \item Highly scriptable

   475           \item Embed in Traits UIs (wxPython and PyQt4)

   476           \item Envisage Plugins

   477           \item Debian/Ubuntu/Fedora

   478           \item \alert{Pythonic}

   479       \end{itemize}

   480     

   481       \inctime{10}

   482 

   483 \end{frame}

   484 

   485 \begin{frame}

   486     {Getting hands dirty!}

   487 

   488         \begin{block}{Motivational problem}

   489         Atmospheric data of temperature over the surface of the earth.

   490         Let temperature ($T$) vary linearly with height ($z$):

   491         \begin{center}            

   492         $T = 288.15 - 6.5z$

   493         \end{center}

   494         \end{block}

   495 \end{frame}

   496 

   497 \begin{frame}[fragile]

   498     \frametitle{Simple solution}

   499 

   500     \begin{lstlisting}

   501 lat = linspace(-89, 89, 37)

   502 lon = linspace(0, 360, 37)

   503 z = linspace(0, 100, 11)

   504     \end{lstlisting}

   505 \pause

   506     \begin{lstlisting}

   507 x, y, z = mgrid[0:360:37j,-89:89:37j,

   508                 0:100:11j]

   509 t = 288.15 - 6.5*z

   510 mlab.contour3d(x, y, z, t)

   511 mlab.outline()

   512 mlab.colorbar()

   513     \end{lstlisting}

   514 \end{frame}

   515 

   516 \begin{frame}[fragile]

   517     \frametitle{Exercise: Lorenz equation}

   518     \begin{columns}

   519         \column{0.25\textwidth}

   520         \begin{eqnarray*}

   521         \frac{d x}{dt} &=& s (y-x)\\

   522         \frac{d y}{d t} &=& rx -y -xz\\

   523         \frac{d z}{d t} &=& xy - bz\\

   524         \end{eqnarray*}

   525         \column{0.25\textwidth}

   526         Let $s=10,$

   527         $r=28,$ 

   528         $b=8./3.$

   529     \end{columns}

   530     \structure{\Large Region of interest}

   531   \begin{lstlisting}

   532 x, y, z = mgrid[-50:50:20j,-50:50:20j,

   533                 -10:60:20j]

   534   \end{lstlisting}

   535 \inctime{20}

   536 

   537 \end{frame}

   538 \begin{frame}[fragile]

   539     \frametitle{Solution}

   540   \begin{lstlisting}

   541 def lorenz(x,y,z,s=10.,r=28.,b=8./3.):

   542     u = s*(y-x)

   543     v = r*x-y-x*z

   544     w = x*y-b*z

   545     return u,v,w

   546 x,y,z = mgrid [-50:50:20j,-50:50:20j,

   547                     -10:60:20j ]

   548 u,v,w = lorenz( x , y , z )

   549 # Your plot here

   550 #

   551 mlab.show()

   552 

   553   \end{lstlisting}

   554 \end{frame}

   555   

   556 \end{document}

   557