# HG changeset patch # User Shantanu # Date 1257307828 -19800 # Node ID 8a4a1e5aec857cc567aaedcdcc2ae25140bf11ae # Parent 9664eddee075c65a90635c33cda671fdb0a7919e Changes made for Goa workshop . diff -r 9664eddee075 -r 8a4a1e5aec85 day1/data/interpolate.png Binary file day1/data/interpolate.png has changed diff -r 9664eddee075 -r 8a4a1e5aec85 day1/session2.tex --- a/day1/session2.tex Sat Oct 31 01:33:41 2009 +0530 +++ b/day1/session2.tex Wed Nov 04 09:40:28 2009 +0530 @@ -260,6 +260,7 @@ \end{lstlisting} \end{frame} +%% more on list slicing \begin{frame}[fragile] \frametitle{List operations} \begin{lstlisting} diff -r 9664eddee075 -r 8a4a1e5aec85 day1/session3.tex --- a/day1/session3.tex Sat Oct 31 01:33:41 2009 +0530 +++ b/day1/session3.tex Wed Nov 04 09:40:28 2009 +0530 @@ -581,6 +581,7 @@ \end{itemize} \end{frame} +%%making vander without vander, simple matrix \subsection{Van der Monde matrix generation} \begin{frame}[fragile] \frametitle{Van der Monde Matrix} diff -r 9664eddee075 -r 8a4a1e5aec85 day1/session4.tex --- a/day1/session4.tex Sat Oct 31 01:33:41 2009 +0530 +++ b/day1/session4.tex Wed Nov 04 09:40:28 2009 +0530 @@ -128,45 +128,68 @@ \begin{frame} \frametitle{Matrices: Introduction} -We looked at the Van der Monde matrix in the previous session,\\ -let us now look at matrices in a little more detail. +Let us now look at matrices in detail.\\ +\alert{All matrix operations are done using \kwrd{arrays}} \end{frame} \subsection{Initializing} \begin{frame}[fragile] \frametitle{Matrices: Initializing} \begin{lstlisting} -In []: A = matrix([[ 1, 1, 2, -1], - [ 2, 5, -1, -9], - [ 2, 1, -1, 3], - [ 1, -3, 2, 7]]) +In []: A = array([[ 1, 1, 2, -1], + [ 2, 5, -1, -9], + [ 2, 1, -1, 3], + [ 1, -3, 2, 7]]) In []: A Out[]: -matrix([[ 1, 1, 2, -1], - [ 2, 5, -1, -9], - [ 2, 1, -1, 3], - [ 1, -3, 2, 7]]) +array([[ 1, 1, 2, -1], + [ 2, 5, -1, -9], + [ 2, 1, -1, 3], + [ 1, -3, 2, 7]]) \end{lstlisting} \end{frame} +\begin{frame}[fragile] + \frametitle{Accessing elements of matrices} +\begin{small} + \begin{lstlisting} +In []: C = array([[1,1,2], + [2,4,1], + [-1,3,7]]) +In []: C[1,2] +Out[]: 1 + +In []: C[1] +Out[]: array([2, 4, 1]) + +In []: C[1,1] = -2 +In []: C +Out[]: +array([[ 1, 1, 2], + [ 2, -2, 1], + [-1, 3, 7]]) + \end{lstlisting} +\end{small} +\end{frame} + \subsection{Basic Operations} \begin{frame}[fragile] \frametitle{Transpose of a Matrix} \begin{lstlisting} -In []: linalg.transpose(A) +In []: A.T Out[]: -matrix([[ 1, 2, 2, 1], - [ 1, 5, 1, -3], - [ 2, -1, -1, 2], - [-1, -9, 3, 7]]) +array([[ 1, 2, 2, 1], + [ 1, 5, 1, -3], + [ 2, -1, -1, 2], + [-1, -9, 3, 7]]) \end{lstlisting} \end{frame} \begin{frame}[fragile] \frametitle{Sum of all elements} \begin{lstlisting} -In []: linalg.sum(A) +In []: sum(A) Out[]: 12 \end{lstlisting} \end{frame} @@ -174,41 +197,56 @@ \begin{frame}[fragile] \frametitle{Matrix Addition} \begin{lstlisting} -In []: B = matrix([[3,2,-1,5], - [2,-2,4,9], - [-1,0.5,-1,-7], - [9,-5,7,3]]) -In []: linalg.add(A,B) +In []: B = array([[3,2,-1,5], + [2,-2,4,9], + [-1,0.5,-1,-7], + [9,-5,7,3]]) +In []: A + B Out[]: -matrix([[ 4. , 3. , 1. , 4. ], - [ 4. , 3. , 3. , 0. ], - [ 1. , 1.5, -2. , -4. ], - [ 10. , -8. , 9. , 10. ]]) +array([[ 4. , 3. , 1. , 4. ], + [ 4. , 3. , 3. , 0. ], + [ 1. , 1.5, -2. , -4. ], + [ 10. , -8. , 9. , 10. ]]) \end{lstlisting} \end{frame} \begin{frame}[fragile] +\frametitle{Elementwise Multiplication} +\begin{lstlisting} +In []: A*B +Out[]: +array([[ 3. , 2. , -2. , -5. ], + [ 4. , -10. , -4. , -81. ], + [ -2. , 0.5, 1. , -21. ], + [ 9. , 15. , 14. , 21. ]]) + +\end{lstlisting} +\end{frame} + +\begin{frame}[fragile] \frametitle{Matrix Multiplication} \begin{lstlisting} -In []: linalg.multiply(A, B) +In []: dot(A,B) Out[]: -matrix([[ 3. , 2. , -2. , -5. ], - [ 4. , -10. , -4. , -81. ], - [ -2. , 0.5, 1. , -21. ], - [ 9. , 15. , 14. , 21. ]]) +array([[ -6. , 6. , -6. , -3. ], + [-64. , 38.5, -44. , 35. ], + [ 36. , -13.5, 24. , 35. ], + [ 58. , -26. , 34. , -15. ]]) \end{lstlisting} \end{frame} \begin{frame}[fragile] \frametitle{Inverse of a Matrix} +\begin{lstlisting} +In []: inv(A) +\end{lstlisting} \begin{small} \begin{lstlisting} -In []: linalg.inv(A) Out[]: -matrix([[-0.5 , 0.55, -0.15, 0.7 ], - [ 0.75, -0.5 , 0.5 , -0.75], - [ 0.5 , -0.15, -0.05, -0.1 ], - [ 0.25, -0.25, 0.25, -0.25]]) +array([[-0.5 , 0.55, -0.15, 0.7 ], + [ 0.75, -0.5 , 0.5 , -0.75], + [ 0.5 , -0.15, -0.05, -0.1 ], + [ 0.25, -0.25, 0.25, -0.25]]) \end{lstlisting} \end{small} \end{frame} @@ -217,24 +255,25 @@ \frametitle{Determinant} \begin{lstlisting} In []: det(A) -Out[66]: 80.0 +Out[]: 80.0 \end{lstlisting} \end{frame} +%%use S=array(X,Y) \begin{frame}[fragile] -\frametitle{Eigen Values and Eigen Matrix} +\frametitle{Eigenvalues and Eigen Vectors} \begin{small} \begin{lstlisting} -In []: E = matrix([[3,2,4],[2,0,2],[4,2,3]]) +In []: E = array([[3,2,4],[2,0,2],[4,2,3]]) -In []: linalg.eig(E) +In []: eig(E) Out[]: (array([-1., 8., -1.]), - matrix([[-0.74535599, 0.66666667, -0.1931126 ], + array([[-0.74535599, 0.66666667, -0.1931126 ], [ 0.2981424 , 0.33333333, -0.78664085], [ 0.59628479, 0.66666667, 0.58643303]])) -In []: linalg.eigvals(E) +In []: eigvals(E) Out[]: array([-1., 8., -1.]) \end{lstlisting} \end{small} @@ -243,23 +282,23 @@ \begin{frame}[fragile] \frametitle{Computing Norms} \begin{lstlisting} -In []: linalg.norm(E) +In []: norm(E) Out[]: 8.1240384046359608 \end{lstlisting} \end{frame} \begin{frame}[fragile] - \frametitle{Single Value Decomposition} + \frametitle{Singular Value Decomposition} \begin{small} \begin{lstlisting} -In [76]: linalg.svd(E) -Out[76]: -(matrix( +In []: svd(E) +Out[]: +(array( [[ -6.66666667e-01, -1.23702565e-16, 7.45355992e-01], [ -3.33333333e-01, -8.94427191e-01, -2.98142397e-01], [ -6.66666667e-01, 4.47213595e-01, -5.96284794e-01]]), array([ 8., 1., 1.]), - matrix([[-0.66666667, -0.33333333, -0.66666667], + array([[-0.66666667, -0.33333333, -0.66666667], [-0. , 0.89442719, -0.4472136 ], [-0.74535599, 0.2981424 , 0.59628479]])) \end{lstlisting} @@ -289,12 +328,12 @@ \frametitle{Solving using Matrices} Let us now look at how to solve this using \kwrd{matrices} \begin{lstlisting} - In []: A = matrix([[3,2,-1], - [2,-2,4], - [-1, 0.5, -1]]) - In []: b = matrix([[1], [-2], [0]]) - In []: x = linalg.solve(A, b) - In []: Ax = dot(A, x) + In []: A = array([[3,2,-1], + [2,-2,4], + [-1, 0.5, -1]]) + In []: b = array([[1], [-2], [0]]) + In []: x = solve(A, b) + In []: Ax = dot(A,x) \end{lstlisting} \end{frame} @@ -314,9 +353,9 @@ \begin{lstlisting} In []: Ax Out[]: -matrix([[ 1.00000000e+00], - [ -2.00000000e+00], - [ 2.22044605e-16]]) +array([[ 1.00000000e+00], + [ -2.00000000e+00], + [ 2.22044605e-16]]) \end{lstlisting} \begin{block}{} The last term in the matrix is actually \alert{0}!\\ @@ -332,7 +371,74 @@ \subsection{Exercises} \begin{frame}[fragile] -\frametitle{Problem Set 4: Problem 4.1} +\frametitle{Problem 1} +Given the matrix:\\ +\begin{center} +$\begin{bmatrix} +-2 & 2 & 3\\ + 2 & 1 & 6\\ +-1 &-2 & 0\\ +\end{bmatrix}$ +\end{center} +Find: +\begin{itemize} + \item[i] Transpose + \item[ii]Inverse + \item[iii]Determinant + \item[iv] Eigenvalues and Eigen vectors + \item[v] Singular Value decomposition +\end{itemize} +\end{frame} + +\begin{frame}[fragile] +\frametitle{Problem 2} +Given +\begin{center} +A = +$\begin{bmatrix} +-3 & 1 & 5 \\ +1 & 0 & -2 \\ +5 & -2 & 4 \\ +\end{bmatrix}$ +, B = +$\begin{bmatrix} +0 & 9 & -12 \\ +-9 & 0 & 20 \\ +12 & -20 & 0 \\ +\end{bmatrix}$ +\end{center} +Find: +\begin{itemize} + \item[i] Sum of A and B + \item[ii]Elementwise Product of A and B + \item[iii] Matrix product of A and B +\end{itemize} +\end{frame} + +\begin{frame}[fragile] +\frametitle{Solution} +Sum: +$\begin{bmatrix} +-3 & 10 & 7 \\ +-8 & 0 & 18 \\ +17 & -22 & 4 \\ +\end{bmatrix}$ +,\\ Elementwise Product: +$\begin{bmatrix} +0 & 9 & -60 \\ +-9 & 0 & -40 \\ +60 & 40 & 0 \\ +\end{bmatrix}$ +,\\ Matrix product: +$\begin{bmatrix} +51 & -127 & 56 \\ +-24 & 49 & -12 \\ +66 & -35 & -100 \\ +\end{bmatrix}$ +\end{frame} + +\begin{frame}[fragile] +\frametitle{Problem 3} Solve the set of equations: \begin{align*} x + y + 2z -w & = 3\\ @@ -345,37 +451,30 @@ \begin{frame}[fragile] \frametitle{Solution} -Solution: -\begin{lstlisting} +Use \kwrd{solve()} \begin{align*} x & = -5\\ y & = 2\\ z & = 3\\ w & = 0\\ \end{align*} -\end{lstlisting} -\end{frame} - -\begin{frame}[fragile] -\frametitle{Problem 4.2} - \end{frame} \section{Summary} \begin{frame} - \frametitle{Summary} -So what did we learn?? + \frametitle{What did we learn??} \begin{itemize} \item Matrices \begin{itemize} + \item Accessing elements \item Transpose \item Addition \item Multiplication \item Inverse of a matrix \item Determinant - \item Eigen values and Eigen matrix + \item Eigenvalues and Eigen vector \item Norms - \item Single Value Decomposition + \item Singular Value Decomposition \end{itemize} \item Solving linear equations \end{itemize} diff -r 9664eddee075 -r 8a4a1e5aec85 day1/session5.tex --- a/day1/session5.tex Sat Oct 31 01:33:41 2009 +0530 +++ b/day1/session5.tex Wed Nov 04 09:40:28 2009 +0530 @@ -124,8 +124,25 @@ %% % \pausesections %% \end{frame} +\section{\typ{loadtxt}} -\section{\typ{loadtxt}} +\begin{frame}[fragile] + \frametitle{Array slicing} + \begin{lstlisting} +In []: A = array([[ 1, 1, 2, -1], + [ 2, 5, -1, -9], + [ 2, 1, -1, 3], + [ 1, -3, 2, 7]]) + +In []: A[:,0] +Out[]: array([ 1, 2, 2, 1]) + +In []: A[1:3,1:3] +Out[]: +array([[ 5, -1], + [ 1, -1]]) +\end{lstlisting} +\end{frame} \begin{frame}[fragile] \frametitle{\typ{loadtxt}} @@ -134,8 +151,9 @@ \item Each row must have same number of values. \end{itemize} \begin{lstlisting} -In []: L, T = loadtxt('pendulum.txt', - unpack = True) +In []: data = loadtxt('pendulum.txt') +In []: x = data[:, 0] +In []: y = data[:, 1] \end{lstlisting} \end{frame} @@ -151,6 +169,7 @@ \item It contains x,y position of particle. \item Plot the given points. %% \item Interpolate the missing region. +%% load txt the unpack part. \end{itemize} \begin{lstlisting} In []: x, y = loadtxt('points.txt', @@ -195,6 +214,8 @@ %% \end{lstlisting} %% \end{frame} +%%better example, maybe parabola + \begin{frame}[fragile] \frametitle{Spline Interpolation} \begin{small} @@ -223,22 +244,29 @@ \begin{frame}[fragile] \frametitle{\typ{splev}} -To Evaluate a B-spline and it's derivatives +To Evaluate a spline and it's derivatives \begin{lstlisting} -In []: Xnew = arange(0.01,3,0.02) +In []: Xnew = linspace(0.01,3,100) In []: Ynew = splev(Xnew, tck) In []: y.shape Out[]: (40,) In []: Ynew.shape -Out[]: (150,) +Out[]: (100,) -In []: plot(Xnew, Ynew) +In []: plot(Xnew, Ynew, '+') \end{lstlisting} \end{frame} +\begin{frame} + \frametitle{Interpolated data} + \begin{center} + \includegraphics[height=2in, interpolate=true]{data/interpolate} + \end{center} +\end{frame} + %% \begin{frame}[fragile] %% \frametitle{Interpolation \ldots} %% \begin{itemize} @@ -257,8 +285,8 @@ \end{itemize} \begin{center} \begin{tabular}{l l} -$f(x+h)=f(x)+h.f^{'}(x)$ &Forward \\ -$f(x-h)=f(x)-h.f^{'}(x)$ &Backward +$f(x+h)=f(x)+hf^{'}(x)$ &Forward \\ +$f(x-h)=f(x)-hf^{'}(x)$ &Backward \end{tabular} \end{center} \end{frame} @@ -277,7 +305,10 @@ \frametitle{Forward Difference \ldots} \begin{lstlisting} In []: fD = (y[1:] - y[:-1]) / deltax -In []: plot(x, y, x[:-1], fD) +In []: print len(fD) +Out[]: 99 +In []: plot(x, y) +In []: plot(x[:-1], fD) \end{lstlisting} \begin{center} \includegraphics[height=2in, interpolate=true]{data/fwdDiff} @@ -310,27 +341,18 @@ \frametitle{Example \ldots} \begin{itemize} \item Read the file -\item Obtain an array of x, y +\item Obtain an array of X, Y(S) \item Obtain velocity and acceleration \item use \typ{deltaT = 0.05} \end{itemize} \begin{lstlisting} -In []: X = [] -In []: Y = [] -In []: for line in open('location.txt'): - .... points = line.split() - .... X.append(float(points[0])) - .... Y.append(float(points[1])) -In []: S = array([X, Y]) +In []: S = loadtxt('location.txt') \end{lstlisting} \end{frame} \begin{frame}[fragile] \frametitle{Example \ldots} -\begin{itemize} -\item use \typ{deltaT = 0.05} -\end{itemize} \begin{lstlisting} In []: deltaT = 0.05 @@ -345,18 +367,17 @@ \begin{frame}[fragile] \frametitle{Quadrature} -\begin{itemize} -\item We wish to find area under a curve -\item Area under $(sin(x) + x^2)$ in $(0,1)$ -\item scipy has functions to do that -\end{itemize} -\begin{small} - \typ{In []: from scipy.integrate import quad} -\end{small} + +\emphbar{$\int_0^1(sin(x) + x^2)$} + +\typ{In []: from scipy.integrate import quad} + \begin{itemize} \item Inputs - function to integrate, limits \end{itemize} \begin{lstlisting} +%% In []: quad(sin(x)+x**2, 0, 1) +%% NameError: name 'x' is not defined In []: x = 0 In []: quad(sin(x)+x**2, 0, 1) \end{lstlisting} @@ -406,8 +427,7 @@ \end{lstlisting} Returns the integral and an estimate of the absolute error in the result. \begin{itemize} -\item Look at \typ{dblquad} for Double integrals -\item Use \typ{tplquad} for Triple integrals +\item \typ{dblquad}, \typ{tplquad} are available \end{itemize} \end{frame} @@ -419,9 +439,7 @@ \item Functions \begin{itemize} \item Definition - \item Calling - \item Default Arguments - \item Keyword Arguments + \item Calling \end{itemize} \item Quadrature \end{itemize} diff -r 9664eddee075 -r 8a4a1e5aec85 day1/session6.tex --- a/day1/session6.tex Sat Oct 31 01:33:41 2009 +0530 +++ b/day1/session6.tex Wed Nov 04 09:40:28 2009 +0530 @@ -123,6 +123,7 @@ %% % You might wish to add the option [pausesections] %% \end{frame} +%%more exercise on plotting \section{ODEs} \begin{frame}[fragile] @@ -138,7 +139,7 @@ \dot{\theta} &= \omega \\ \dot{\omega} &= -\frac{g}{L}sin(\theta) \\ \text{At}\ t &= 0 : \nonumber \\ - \theta = \theta_0\quad & \&\quad \omega = 0 \nonumber + \theta = \theta_0(10^o)\quad & \&\quad \omega = 0\ (Initial\ values)\nonumber \end{align} \end{frame} @@ -149,9 +150,9 @@ \item Define a function as below \end{itemize} \begin{lstlisting} -In []: def pend_int(unknown, t, p): - .... theta, omega = unknown - .... g, L = p +In []: def pend_int(initial, t): + .... theta, omega = initial + .... g, L = 9.81, 0.2 .... f=[omega, -(g/L)*sin(theta)] .... return f .... @@ -162,25 +163,22 @@ \frametitle{Solving ODEs using SciPy \ldots} \begin{itemize} \item \typ{t} is the time variable \\ -\item \typ{p} has the constants \\ \item \typ{initial} has the initial values \end{itemize} \begin{lstlisting} In []: t = linspace(0, 10, 101) -In []: p=(-9.81, 0.2) In []: initial = [10*2*pi/360, 0] -\end{lstlisting} +\end{lstlisting} \end{frame} \begin{frame}[fragile] \frametitle{Solving ODEs using SciPy \ldots} -\begin{small} - \typ{In []: from scipy.integrate import odeint} -\end{small} +%%\begin{small} +\typ{In []: from scipy.integrate import odeint} +%%\end{small} \begin{lstlisting} In []: pend_sol = odeint(pend_int, - initial,t, - args=(p,)) + initial,t) \end{lstlisting} \end{frame} @@ -308,14 +306,13 @@ \begin{frame}[fragile] \frametitle{Initial Estimates \ldots} \begin{lstlisting} - In []: def our_f(x): - ....: return cos(x)-x**2 - ....: - In []: x = linspace(-pi/2, pi/2, 11) +In []: def our_f(x): + ....: return cos(x) - x*x + ....: +In []: x = linspace(-pi/2, pi/2, 11) +In []: y = our_f(x) \end{lstlisting} -\begin{itemize} -\item Get the intervals of x, where sign changes occur -\end{itemize} +Get the intervals of x, where sign changes occur \end{frame} \begin{frame}[fragile] @@ -335,7 +332,6 @@ \frametitle{Scipy Methods - \typ{roots}} \begin{itemize} \item Calculates the roots of polynomials -\item Array of coefficients is the only parameter \end{itemize} \begin{lstlisting} In []: coeffs = [1, 6, 13] diff -r 9664eddee075 -r 8a4a1e5aec85 day1quiz1.tex --- a/day1quiz1.tex Sat Oct 31 01:33:41 2009 +0530 +++ b/day1quiz1.tex Wed Nov 04 09:40:28 2009 +0530 @@ -129,7 +129,7 @@ \begin{frame} \frametitle{\incqno } -How to read and print each line of file. +How to read and print each line of a file. \end{frame} \begin{frame} @@ -146,5 +146,15 @@ \end{lstlisting} \end{frame} +\begin{frame} +\frametitle{\incqno } +Draw a plot with line width 3. +\end{frame} + +\begin{frame} +\frametitle{\incqno } +Setting x and y axis limits. +\end{frame} + \end{document} diff -r 9664eddee075 -r 8a4a1e5aec85 day2/session3.tex --- a/day2/session3.tex Sat Oct 31 01:33:41 2009 +0530 +++ b/day2/session3.tex Wed Nov 04 09:40:28 2009 +0530 @@ -95,12 +95,12 @@ %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % Title page -\title[]{3D data Visualization} +\title[3D Plotting]{3D data Visualization} \author[FOSSEE] {FOSSEE} \institute[IIT Bombay] {Department of Aerospace Engineering\\IIT Bombay} -\date[] {1, November 2009\\Day 2, Session 3} +\date[] {1 November, 2009\\Day 2, Session 5} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% @@ -279,10 +279,9 @@ \end{columns} \begin{lstlisting} -In []: from numpy import * In []: t = linspace(0, 2*pi, 50) In []: u = cos(t) * pi -in []: x, y, z = sin(u), cos(u), sin(t) +In []: x, y, z = sin(u), cos(u), sin(t) \end{lstlisting} \emphbar{\PythonCode{In []: mlab.points3d(x, y, z)}} \end{frame} @@ -319,6 +318,40 @@ \end{frame} \begin{frame}[fragile] + \frametitle{mgrid} + \begin{lstlisting} +In []: mgrid[0:3,0:3] +Out[]: +array([[[0, 0, 0], + [1, 1, 1], + [2, 2, 2]], + + [[0, 1, 2], + [0, 1, 2], + [0, 1, 2]]]) + +In []: mgrid[-1:1:5j] +Out[]: array([-1., -0.5, 0., 0.5, 1.]) +\end{lstlisting} +\end{frame} + +\begin{frame}[fragile] + \frametitle{Example} + \begin{lstlisting} +In []: x, y = mgrid[-1:1:5j, -1:1:5j] +In []: z = x*x + y*y + +In []: z +Out[]: +array([[ 2. , 1.25, 1. , 1.25, 2. ], + [ 1.25, 0.5 , 0.25, 0.5 , 1.25], + [ 1. , 0.25, 0. , 0.25, 1. ], + [ 1.25, 0.5 , 0.25, 0.5 , 1.25], + [ 2. , 1.25, 1. , 1.25, 2. ]]) +\end{lstlisting} +\end{frame} + +\begin{frame}[fragile] \myemph{\Large 2D data: \texttt{mlab.mesh}} \vspace*{0.25in} @@ -328,7 +361,7 @@ \vspace*{0.25in} \begin{lstlisting} -In []: phi, theta = numpy.mgrid[0:pi:20j, +In []: phi, theta = mgrid[0:pi:20j, ... 0:2*pi:20j] In []: x = sin(phi)*cos(theta) In []: y = sin(phi)*sin(theta) @@ -349,7 +382,7 @@ \pgfimage[width=1.5in]{MEDIA/m2/mlab/contour3d}\\ \end{columns} \begin{lstlisting} -In []: x, y, z = ogrid[-5:5:64j, +In []: x, y, z = mgrid[-5:5:64j, ... -5:5:64j, ... -5:5:64j] In []: mlab.contour3d(x*x*0.5 + y*y + diff -r 9664eddee075 -r 8a4a1e5aec85 day2/session4.tex --- a/day2/session4.tex Sat Oct 31 01:33:41 2009 +0530 +++ b/day2/session4.tex Wed Nov 04 09:40:28 2009 +0530 @@ -95,14 +95,12 @@ %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % Title page -\title[]{Debugging and \\Test Driven Approach} +\title[Python Development]{Python Development} \author[FOSSEE] {FOSSEE} \institute[IIT Bombay] {Department of Aerospace Engineering\\IIT Bombay} -\date[] {11, October 2009} -\date[] % (optional) - +\date[] {1 November, 2009\\Day 2, Session 3} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %\pgfdeclareimage[height=0.75cm]{iitblogo}{iitblogo} @@ -142,13 +140,147 @@ \maketitle \end{frame} +\section{Tests: Getting started} +\begin{frame}[fragile] + \frametitle{gcd revisited!} + \begin{itemize} + \item Open gcd.py + \end{itemize} +\begin{lstlisting} + def gcd(a, b): + if a % b == 0: + return b + return gcd(b, a%b) + + print gcd(15, 65) + print gcd(16, 76) +\end{lstlisting} + \begin{itemize} + \item python gcd.py + \end{itemize} +\end{frame} + +\begin{frame}[fragile] + \frametitle{Find lcm using our gcd module} + \begin{itemize} + \item Open lcm.py + \item $lcm = \frac{a*b}{gcd(a,b)}$ + \end{itemize} +\begin{lstlisting} + from gcd import gcd + def lcm(a, b): + return (a * b) / gcd(a, b) + + print lcm(14, 56) +\end{lstlisting} + \begin{itemize} + \item python lcm.py + \end{itemize} + \begin{lstlisting} +5 +4 +56 + \end{lstlisting} +\end{frame} + +\begin{frame}[fragile] + \frametitle{Writing stand-alone module} +Edit gcd.py file to: +\begin{lstlisting} + def gcd(a, b): + if a % b == 0: + return b + return gcd(b, a%b) + + if __name__ == "__main__": + print gcd(15, 65) + print gcd(16, 76) +\end{lstlisting} + \begin{itemize} + \item python gcd.py + \item python lcm.py + \end{itemize} +\end{frame} + +\begin{frame}[fragile] + \frametitle{More use of main} + For automating tests. + \begin{lstlisting} +if __name__ == '__main__': + for line in open('numbers.txt'): + numbers = line.split() + x = int(numbers[0]) + y = int(numbers[1]) + result = (int(numbers[2])) + assert gcd(x, y) == result + \end{lstlisting} +\end{frame} + +\section{Coding Style} +\begin{frame}{Readability and Consistency} + \begin{itemize} + \item Readability Counts!\\Code is read more often than its written. + \item Consistency! + \item Know when to be inconsistent. + \end{itemize} +\end{frame} + +\begin{frame}[fragile] \frametitle{A question of good style} + \begin{lstlisting} + amount = 12.68 + denom = 0.05 + nCoins = round(amount/denom) + rAmount = nCoins * denom + \end{lstlisting} + \pause + \begin{block}{Style Rule \#1} + Naming is 80\% of programming + \end{block} +\end{frame} + +\begin{frame}[fragile] + \frametitle{Code Layout} + \begin{itemize} + \item Indentation + \item Tabs or Spaces?? + \item Maximum Line Length + \item Blank Lines + \item Encodings + \end{itemize} +\end{frame} + +\begin{frame}{Whitespaces in Expressions} + \begin{itemize} + \item When to use extraneous whitespaces?? + \item When to avoid extra whitespaces?? + \item Use one statement per line + \end{itemize} +\end{frame} + +\begin{frame}{Comments} + \begin{itemize} + \item No comments better than contradicting comments + \item Block comments + \item Inline comments + \end{itemize} +\end{frame} + +\begin{frame}{Docstrings} + \begin{itemize} + \item When to write docstrings? + \item Ending the docstrings + \item One liner docstrings + \end{itemize} +More information at PEP8: http://www.python.org/dev/peps/pep-0008/ +\inctime{5} +\end{frame} \section{Debugging} \subsection{Errors and Exceptions} \begin{frame}[fragile] \frametitle{Errors} \begin{lstlisting} ->>> while True print 'Hello world' +In []: while True print 'Hello world' \end{lstlisting} \pause \begin{lstlisting} @@ -162,7 +294,7 @@ \begin{frame}[fragile] \frametitle{Exceptions} \begin{lstlisting} ->>> print spam +In []: print spam \end{lstlisting} \pause \begin{lstlisting} @@ -175,7 +307,7 @@ \begin{frame}[fragile] \frametitle{Exceptions} \begin{lstlisting} ->>> 1 / 0 +In []: 1 / 0 \end{lstlisting} \pause \begin{lstlisting} @@ -186,6 +318,44 @@ \end{lstlisting} \end{frame} +\begin{frame}[fragile] + \frametitle{Handling Exceptions} + Python uses \typ{try} and \typ{except} clause. + %%Revisiting the raw\_input + \begin{lstlisting} +a = raw_input('Enter number(Q to quit):') +try: + num = int(a) + print num +except: + if a == 'Q': + print 'Exiting...' + else: + print 'Wrong input!' + \end{lstlisting} + + +\end{frame} + +%% \begin{frame}[fragile] +%% \frametitle{Solving it with \typ{try} and \typ{except}} +%% \vspace{-0.2in} +%% \begin{lstlisting} +%% highest = 0 +%% for record in open('sslc1.txt'): +%% fields = record.split(';') +%% try: +%% total = 0 +%% for score_str in fields[3:8]: +%% score = int(score_str) +%% total += score +%% if total > highest: +%% highest = total +%% except: +%% pass +%% print highest +%% \end{lstlisting} +%% \end{frame} \subsection{Strategy} \begin{frame}[fragile] \frametitle{Debugging effectively} @@ -209,8 +379,8 @@ \frametitle{Debugging in IPython} \small \begin{lstlisting} -In [1]: import mymodule -In [2]: mymodule.test() +In []: import mymodule +In []: mymodule.test() --------------------------------------------- NameError Traceback (most recent call last) in () @@ -219,7 +389,7 @@ ----> 2 print spam NameError: global name 'spam' is not defined -In [3]: %debug +In []: %debug > mymodule.py(2)test() 0 print spam ipdb> @@ -232,19 +402,21 @@ \frametitle{Debugging: Exercise} \small \begin{lstlisting} -import keyword -f = open('/path/to/file') +science = {} + +for record in open('sslc1.txt'): + fields = record.split(';') + region_code = fields[0].strip() -freq = {} -for line in f: - words = line.split() - for word in words: - key = word.strip(',.!;?()[]: ') - if keyword.iskeyword(key): - value = freq[key] - freq[key] = value + 1 + score_str = fields[6].strip() + score = int(score_str) if score_str != 'AA' + else 0 -print freq + if score > 90: + science[region_code] += 1 + +pie(science.values(), labels=science.keys()) +savefig('science.png') \end{lstlisting} \inctime{10} \end{frame} @@ -263,7 +435,7 @@ \section{Test Driven Approach} \begin{frame} - \frametitle{Need of Testing!} + \frametitle{Need for Testing!} \begin{itemize} \item Quality @@ -293,17 +465,19 @@ \begin{frame}[fragile] \frametitle{Test for the palindrome: palindrome.py} \begin{lstlisting} -from plaindrome import is_palindrome def test_function_normal_words(): input = "noon" assert is_palindrome(input) == True + +if __name__ == "main'': + test_function_normal_words() \end{lstlisting} \end{frame} \begin{frame}[fragile] \frametitle{Running the tests.} \begin{lstlisting} -$ nosetests test.py +$ nosetests palindrome.py . ---------------------------------------------- Ran 1 test in 0.001s @@ -321,7 +495,7 @@ \end{lstlisting} \vspace*{0.25in} Check\\ - \PythonCode{$ nosetests test.py} \\ + \PythonCode{$ nosetests palindrome.py} \\ \begin{block}{Task} Tweak the code to pass this test. \end{block} @@ -347,37 +521,39 @@ %\end{frame} % -\begin{frame}[fragile] - \frametitle{Exercise} - Based on Euclid's algorithm: - \begin{center} - $gcd(a,b)=gcd(b,b\%a)$ - \end{center} - gcd function can be written as: - \begin{lstlisting} - def gcd(a, b): - if a%b == 0: return b - return gcd(b, a%b) - \end{lstlisting} - \vspace*{-0.15in} - \begin{block}{Task} - \begin{itemize} - \item Write at least - two tests for above mentioned function. - \item Write a non recursive implementation - of gcd(), and test it using already - written tests. - \end{itemize} - \end{block} +%% \begin{frame}[fragile] +%% \frametitle{Exercise} +%% Based on Euclid's algorithm: +%% \begin{center} +%% $gcd(a,b)=gcd(b,b\%a)$ +%% \end{center} +%% gcd function can be written as: +%% \begin{lstlisting} +%% def gcd(a, b): +%% if a%b == 0: return b +%% return gcd(b, a%b) +%% \end{lstlisting} +%% \vspace*{-0.15in} +%% \begin{block}{Task} +%% \begin{itemize} +%% \item Write at least +%% two tests for above mentioned function. +%% \item Write a non recursive implementation +%% of gcd(), and test it using already +%% written tests. +%% \end{itemize} +%% \end{block} -\inctime{15} -\end{frame} +%% \inctime{15} +%% \end{frame} \begin{frame} - \frametitle{We have learned} + \frametitle{Summary} +We have coverd: \begin{itemize} \item Following and Resolving Error Messages. \item Exceptions. + \item Handling exceptions \item Approach for Debugging. \item Writting and running tests. \end{itemize} diff -r 9664eddee075 -r 8a4a1e5aec85 day2/session5.tex --- a/day2/session5.tex Sat Oct 31 01:33:41 2009 +0530 +++ b/day2/session5.tex Wed Nov 04 09:40:28 2009 +0530 @@ -78,7 +78,7 @@ \author[FOSSEE] {FOSSEE} \institute[IIT Bombay] {Department of Aerospace Engineering\\IIT Bombay} -\date[] {1, November 2009\\Day 2} +\date[] {1 November, 2009\\Day 2, Session 4} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %\pgfdeclareimage[height=0.75cm]{iitmlogo}{iitmlogo} @@ -111,12 +111,13 @@ \end{frame} \begin{frame}{Problem 1.1} - The aliquot of a number is defined as: the sum of the \emph{proper} divisors of the number. For example, aliquot(12) = 1 + 2 + 3 + 4 + 6 = 16.\\ + The aliquot of a number is defined as: the sum of the \emph{proper} divisors of the number. \\For example: +\center{aliquot(12) = 1 + 2 + 3 + 4 + 6 = 16.}\\ Write a function that returns the aliquot number of a given number. \end{frame} \begin{frame}{Problem 1.2} - A pair of numbers (a, b) is said to be \alert{amicable} if the aliquot number of a is b and the aliquot number of b is a.\\ + Pair of numbers (a, b) is said to be \alert{amicable} if aliquot number of a is b and aliquot number of b is a.\\ Example: \texttt{220, 284}\\ Write a program that prints all four digit amicable pairs.