# HG changeset patch
# User Puneeth Chaganti <punchagan@fossee.in>
# Date 1289421254 -19800
# Node ID 9a1c5d134feb1f38b8f53d305989217179e840d5
# Parent  2ce824b5adf4909a1fa856702596e82ec1bc1f63
Reviewed getting started with symbolics.

diff -r 2ce824b5adf4 -r 9a1c5d134feb getting-started-with-symbolics/script.rst
--- a/getting-started-with-symbolics/script.rst	Wed Nov 10 19:00:23 2010 +0530
+++ b/getting-started-with-symbolics/script.rst	Thu Nov 11 02:04:14 2010 +0530
@@ -25,66 +25,65 @@
 Symbolics with Sage
 -------------------
 
-Hello friends and welcome to the tutorial on symbolics with sage.
+Hello friends and welcome to the tutorial on Symbolics with Sage.
 
 {{{ Show welcome slide }}}
 
-
-.. #[Madhu: What is this line doing here. I don't see much use of it]
-
 During the course of the tutorial we will learn
 
 {{{ Show outline slide  }}}
 
-* Defining symbolic expressions in sage.  
+* Defining symbolic expressions in Sage.  
 * Using built-in constants and functions. 
-* Performing Integration, differentiation using sage. 
+* Performing Integration, differentiation using Sage. 
 * Defining matrices. 
-* Defining Symbolic functions.  
+* Defining symbolic functions.  
 * Simplifying and solving symbolic expressions and functions.
 
-We can use Sage for symbolic maths. 
+Amongst a lot of other things, Sage can do Symbolic Math and we shall
+start with defining symbolic expressions in Sage. 
+
+Hope you have your Sage notebook open. If not, pause the video and
+start you Sage notebook. 
 
 On the sage notebook type::
    
     sin(y)
 
-It raises a name error saying that y is not defined. But in sage we
-can declare y as a symbol using var function.
+It raises a name error saying that ``y`` is not defined. We need to
+declare ``y`` as a symbol. We do it using the ``var`` function. 
+::
 
-
-::
     var('y')
    
 Now if you type::
 
     sin(y)
 
-sage simply returns the expression.
-
+Sage simply returns the expression.
 
-Thus sage treats sin(y) as a symbolic expression . We can use
-this to do  symbolic maths using sage's built-in constants and
-expressions..
+Sage treats ``sin(y)`` as a symbolic expression. We can use this to do
+symbolic maths using Sage's built-in constants and expressions.
 
-
-So let us try ::
+Let us try out a few examples. ::
    
    var('x,alpha,y,beta') 
    x^2/alpha^2+y^2/beta^2
+
+We have defined 4 variables, ``x``, ``y``, ``alpha`` and ``beta`` and
+have defined a symbolic expression using them.
  
-taking another example ::
+Here is an expression in ``theta``  ::
    
    var('theta')
    sin(theta)*sin(theta)+cos(theta)*cos(theta)
 
-Similarly, we can define many algebraic and trigonometric expressions using sage .
-
+Now that you know how to define symbolic expressions in Sage, here is
+an exercise. 
 
-Following is an exercise that you must do. 
+{{ show slide showing question 1 }}
 
-%% %%  Define following expressions as symbolic expressions
-in sage?
+%% %% Define following expressions as symbolic expressions in Sage. 
    
    1. x^2+y^2
    #. y^2-4ax
@@ -93,42 +92,37 @@
 
 The solution is on your screen.
 
-
-Sage also provides a few built-in constants which are commonly used in mathematics .
-
-example : pi,e,infinity , Function n gives the numerical values of all these constants.
+{{ show slide showing solution 1 }}
 
-{{{ Type n(pi) n(e) n(oo) On the sage notebook }}}
-
-
-
-If you look into the documentation of function "n" by doing
-
-.. #[Madhu: "documentation of the function "n"?]
+Sage also provides built-in constants which are commonly used in
+mathematics, for instance pi, e, infinity. The function ``n`` gives
+the numerical values of all these constants.
+:: 
+    n(pi) 
+    n(e) 
+    n(oo)
+   
+If you look into the documentation of function ``n`` by doing
 
 ::
    n(<Tab>
 
-You will see what all arguments it takes and what it returns. It will be very
-helpful if you look at the documentation of all functions introduced through
-this script.
-
-
+You will see what all arguments it takes and what it returns. It will
+be very helpful if you look at the documentation of all functions
+introduced in the course of this script.
 
-Also we can define the no. of digits we wish to use in the numerical
-value . For this we have to pass an argument digits.  Type
+Also we can define the number of digits we wish to have in the
+constants. For this we have to pass an argument -- digits.  Type
 
-.. #[Madhu: "no of digits"? Also "We wish to obtain" than "we wish to
-     use"?]
 ::
 
    n(pi, digits = 10)
 
-Apart from the constants sage also has a lot of builtin functions like
-sin,cos,log,factorial,gamma,exp,arcsin etc ...
-lets try some of them out on the sage notebook.
+Apart from the constants Sage also has a lot of built-in functions
+like ``sin``, ``cos``, ``log``, ``factorial``, ``gamma``, ``exp``,
+``arcsin`` etc ...
 
-
+Lets try some of them out on the Sage notebook.
 ::
      
    sin(pi/2)
@@ -137,9 +131,12 @@
      
    log(e,e)
 
-Following is are exercises that you must do. 
+Following are exercises that you must do. 
 
-%% %% Find the values of the following constants upto 6 digits  precision 
+{{ show slide showing question 2 }}
+
+%% %% Find the values of the following constants upto 6 digits
+      precision
    
    1. pi^2
    #. euler_gamma^2
@@ -150,19 +147,18 @@
    1. sin(pi/4)
    #. ln(23)  
 
-Please, pause the video here. Do the exercises and then continue. 
+Please, pause the video here. Do the exercises and then continue.
 
-The solutions are on your screen.
+The solutions are on your screen
 
-
+{{ show slide showing solution 2 }}
 
-Given that we have defined variables like x,y etc .. , We can define
-an arbitrary function with desired name in the following way.::
+Given that we have defined variables like x, y etc., we can define an
+arbitrary function with desired name in the following way.::
 
        var('x') 
        function('f',x)
 
-
 Here f is the name of the function and x is the independent variable .
 Now we can define f(x) to be ::
 
@@ -174,29 +170,18 @@
 
 We can also define functions that are not continuous but defined
 piecewise.  Let us define a function which is a parabola between 0
-to 1 and a constant from 1 to 2 .  Type the following as given on the
-screen
-
+to 1 and a constant from 1 to 2 .  Type the following 
 ::
       
 
       var('x') 
       h(x)=x^2 
       g(x)=1 
-      f=Piecewise(<Tab>
 
-{{{ Show the documentation of Piecewise }}} 
-    
-::
       f=Piecewise([[(0,1),h(x)],[(1,2),g(x)]],x) 
       f
 
-
-
-
-
-We can also define functions which are series 
-
+We can also define functions convergent series and other series. 
 
 We first define a function f(n) in the way discussed above.::
 
@@ -221,11 +206,11 @@
     f(n) = (-1)^(n-1)*1/(2*n - 1)
     sum(f(n), n, 1, oo)
 
-
 This series converges to pi/4. 
 
+Following  are exercises that you must do. 
 
-Following  are exercises that you must do. 
+{{ show slide showing question 3 }}
 
 %% %% Define the piecewise function. 
    f(x)=3x+2 
@@ -237,14 +222,15 @@
 
 Please, pause the video here. Do the exercise(s) and then continue. 
 
+{{ show slide showing solution 3 }}
+
 Moving on let us see how to perform simple calculus operations using Sage
 
 For example lets try an expression first ::
 
     diff(x**2+sin(x),x) 
-    2x+cos(x)
 
-The diff function differentiates an expression or a function. Its
+The diff function differentiates an expression or a function. It's
 first argument is expression or function and second argument is the
 independent variable.
 
@@ -256,44 +242,40 @@
 To get a higher order differential we need to add an extra third argument
 for order ::
  
-   diff(<tab> diff(f(x),x,3)
+   diff(f(x),x,3)
 
 in this case it is 3.
 
-
 Just like differentiation of expression you can also integrate them ::
 
      x = var('x') 
      s = integral(1/(1 + (tan(x))**2),x) 
      s
 
-
-
-Many a times we need to find factors of an expression ,we can use the "factor" function
+Many a times we need to find factors of an expression, we can use the
+"factor" function
 
 ::
-    factor(<tab> 
+
     y = (x^100 - x^70)*(cos(x)^2 + cos(x)^2*tan(x)^2) 
     f = factor(y)
 
-One can  simplify complicated expression ::
+One can simplify complicated expression ::
     
     f.simplify_full()
 
-This simplifies the expression fully . We can also do simplification
-of just the algebraic part and the trigonometric part ::
+This simplifies the expression fully. We can also do simplification of
+just the algebraic part and the trigonometric part ::
 
     f.simplify_exp() 
     f.simplify_trig()
     
-
-
-One can also find roots of an equation by using find_root function::
+One can also find roots of an equation by using ``find_root`` function::
 
     phi = var('phi') 
     find_root(cos(phi)==sin(phi),0,pi/2)
 
-Lets substitute this solution into the equation and see we were
+Let's substitute this solution into the equation and see we were
 correct ::
 
      var('phi') 
@@ -322,18 +304,13 @@
 Please, pause the video here. Do the exercises and then continue. 
 
 
-
 Lets us now try some matrix algebra symbolically ::
 
-
-
    var('a,b,c,d') 
    A=matrix([[a,1,0],[0,b,0],[0,c,d]]) 
    A
 
 Now lets do some of the matrix operations on this matrix
-
-
 ::
     A.det() 
     A.inverse()
@@ -348,17 +325,15 @@
 Please, pause the video here. Do the exercise(s) and then continue. 
 
 
-
-
 {{{ Show the summary slide }}}
 
-So in this tutorial we learnt how to
-
+That brings us to the end of this tutorial. In this tutorial we learnt
+how to
 
-* We learnt about defining symbolic expression and functions.  
-* Using built-in constants and functions.  
-* Using <Tab>  to see the documentation of a function.  
-* Simple calculus operations .  
-* Substituting values in expression using substitute function.
-* Creating symbolic matrices and performing operation on them .
+* define symbolic expression and functions
+* use built-in constants and functions  
+* use <Tab> to see the documentation of a function  
+* do simple calculus
+* substitute values in expressions using ``substitute`` function
+* create symbolic matrices and perform operations on them
 
diff -r 2ce824b5adf4 -r 9a1c5d134feb getting-started-with-symbolics/slides.org
--- a/getting-started-with-symbolics/slides.org	Wed Nov 10 19:00:23 2010 +0530
+++ b/getting-started-with-symbolics/slides.org	Thu Nov 11 02:04:14 2010 +0530
@@ -37,14 +37,14 @@
   - Defining Symbolic functions.  
   - Simplifying and solving symbolic expressions and functions.
 
-* Questions 1
+* Question 1
   - Define the following expression as symbolic
     expression in sage.
 
     - x^2+y^2
     - y^2-4ax
   
-* Solutions 1
+* Solution 1
 #+begin_src python
   var('x,y')
   x^2+y^2
@@ -52,10 +52,11 @@
   var('a,x,y')
   y^2-4*a*x
 #+end_src python
-* Questions 2
+* Question 2
   - Find the values of the following constants upto 6 digits  precision 
    
     - pi^2
+    - euler_gamma^2
    
       
   - Find the value of the following.
@@ -63,13 +64,13 @@
    - sin(pi/4)
    - ln(23)  
 
-* Solutions 2
+* Solution 2
 #+begin_src python
   n(pi^2,digits=6)
   n(sin(pi/4))
   n(log(23,e))
 #+end_src python
-* Question 2
+* Question 3
   - Define the piecewise function. 
    f(x)=3x+2 
    when x is in the closed interval 0 to 4.
@@ -78,7 +79,7 @@
    
   - Sum  of 1/(n^2-1) where n ranges from 1 to infinity. 
 
-* Solution Q1
+* Solution 3
 #+begin_src python
   var('x') 
   h(x)=3*x+2 
@@ -86,18 +87,18 @@
   f=Piecewise([[(0,4),h(x)],[(4,6),g(x)]],x)
   f
 #+end_src python
-* Solution Q2
+
 #+begin_src python  
   var('n')
   f=1/(n^2-1) 
   sum(f(n), n, 1, oo)
 #+end_src python  
- 
 
-* Questions 3
+* Question 4
   - Differentiate the following. 
       
-    - x^5*log(x^7)  , degree=4 
+    - sin(x^3)+log(3x), to the second order
+    - x^5*log(x^7), to the fourth order
 
   - Integrate the given expression 
       
@@ -107,7 +108,7 @@
     - cos(x^2)-log(x)=0
     - Does the equation have a root between 1,2. 
 
-* Solutions 3
+* Solution 4
 #+begin_src python
   var('x')
   f(x)= x^5*log(x^7) 
@@ -121,12 +122,12 @@
   find_root(f(x)==0,1,2)
 #+end_src
 
-* Question 4
+* Question 5
   - Find the determinant and inverse of :
 
       A=[[x,0,1][y,1,0][z,0,y]]
 
-* Solution 4
+* Solution 5
 #+begin_src python  
   var('x,y,z')
   A=matrix([[x,0,1],[y,1,0],[z,0,y]])
@@ -134,19 +135,12 @@
   A.inverse()
 #+end_src
 * Summary
- - We learnt about defining symbolic 
-   expression and functions.  
- - Using built-in constants and functions.  
- - Using <Tab>  to see the documentation of a 
-   function.  
- 
-* Summary 
- - Simple calculus operations .  
- - Substituting values in expression 
-   using substitute function.
- - Creating symbolic matrices and 
-   performing operation on them .
-
+ - We learnt about defining symbolic expression and functions.
+ - Using built-in constants and functions.
+ - Using <Tab> to see the documentation of a function.
+ - Simple calculus operations .
+ - Substituting values in expression using substitute function.
+ - Creating symbolic matrices and performing operation on them .
 * Thank you!
 #+begin_latex
   \begin{block}{}
diff -r 2ce824b5adf4 -r 9a1c5d134feb getting-started-with-symbolics/slides.tex
--- a/getting-started-with-symbolics/slides.tex	Wed Nov 10 19:00:23 2010 +0530
+++ b/getting-started-with-symbolics/slides.tex	Thu Nov 11 02:04:14 2010 +0530
@@ -1,4 +1,4 @@
-% Created 2010-11-10 Wed 17:18
+% Created 2010-11-11 Thu 02:03
 \documentclass[presentation]{beamer}
 \usepackage[latin1]{inputenc}
 \usepackage[T1]{fontenc}
@@ -8,7 +8,6 @@
 \usepackage{float}
 \usepackage{wrapfig}
 \usepackage{soul}
-\usepackage{t1enc}
 \usepackage{textcomp}
 \usepackage{marvosym}
 \usepackage{wasysym}
@@ -55,7 +54,7 @@
 \end{itemize}
 \end{frame}
 \begin{frame}
-\frametitle{Questions 1}
+\frametitle{Question 1}
 \label{sec-2}
 
 \begin{itemize}
@@ -72,28 +71,34 @@
   
 \end{frame}
 \begin{frame}[fragile]
-\frametitle{Solutions 1}
+\frametitle{Solution 1}
 \label{sec-3}
 
-\begin{verbatim}
+\lstset{language=Python}
+\begin{lstlisting}
 var('x,y')
 x^2+y^2
 
 var('a,x,y')
 y^2-4*a*x
-\end{verbatim}
+\end{lstlisting}
 \end{frame}
 \begin{frame}
-\frametitle{Questions 2}
+\frametitle{Question 2}
 \label{sec-4}
 
+
 \begin{itemize}
 \item Find the values of the following constants upto 6 digits  precision
 
 \begin{itemize}
 \item pi$^2$
+\item euler$_{\mathrm{gamma}}$$^2$
 \end{itemize}
 
+\end{itemize}
+
+\begin{itemize}
 \item Find the value of the following.
 
 \begin{itemize}
@@ -104,17 +109,18 @@
 \end{itemize}
 \end{frame}
 \begin{frame}[fragile]
-\frametitle{Solutions 2}
+\frametitle{Solution 2}
 \label{sec-5}
 
-\begin{verbatim}
+\lstset{language=Python}
+\begin{lstlisting}
 n(pi^2,digits=6)
 n(sin(pi/4))
 n(log(23,e))
-\end{verbatim}
+\end{lstlisting}
 \end{frame}
 \begin{frame}
-\frametitle{Question 2}
+\frametitle{Question 3}
 \label{sec-6}
 
 \begin{itemize}
@@ -127,37 +133,35 @@
 \end{itemize}
 \end{frame}
 \begin{frame}[fragile]
-\frametitle{Solution Q1}
+\frametitle{Solution 3}
 \label{sec-7}
 
-\begin{verbatim}
+\lstset{language=Python}
+\begin{lstlisting}
 var('x') 
 h(x)=3*x+2 
 g(x)= 4*x^2
 f=Piecewise([[(0,4),h(x)],[(4,6),g(x)]],x)
 f
-\end{verbatim}
-\end{frame}
-\begin{frame}[fragile]
-\frametitle{Solution Q2}
-\label{sec-8}
+\end{lstlisting}
 
-\begin{verbatim}
+\lstset{language=Python}
+\begin{lstlisting}
 var('n')
 f=1/(n^2-1) 
 sum(f(n), n, 1, oo)
-\end{verbatim}
- 
+\end{lstlisting}
 \end{frame}
 \begin{frame}
-\frametitle{Questions 3}
-\label{sec-9}
+\frametitle{Question 4}
+\label{sec-8}
 
 \begin{itemize}
 \item Differentiate the following.
 
 \begin{itemize}
-\item x$^5$*log(x$^7$)  , degree=4
+\item sin(x$^3$)+log(3x), to the second order
+\item x$^5$*log(x$^7$), to the fourth order
 \end{itemize}
 
 \item Integrate the given expression
@@ -176,10 +180,11 @@
 \end{itemize}
 \end{frame}
 \begin{frame}[fragile]
-\frametitle{Solutions 3}
-\label{sec-10}
+\frametitle{Solution 4}
+\label{sec-9}
 
-\begin{verbatim}
+\lstset{language=Python}
+\begin{lstlisting}
 var('x')
 f(x)= x^5*log(x^7) 
 diff(f(x),x,5)
@@ -190,11 +195,11 @@
 var('x')
 f=cos(x^2)-log(x)
 find_root(f(x)==0,1,2)
-\end{verbatim}
+\end{lstlisting}
 \end{frame}
 \begin{frame}
-\frametitle{Question 4}
-\label{sec-11}
+\frametitle{Question 5}
+\label{sec-10}
 
 \begin{itemize}
 \item Find the determinant and inverse of :
@@ -203,45 +208,33 @@
 \end{itemize}
 \end{frame}
 \begin{frame}[fragile]
-\frametitle{Solution 4}
-\label{sec-12}
+\frametitle{Solution 5}
+\label{sec-11}
 
-\begin{verbatim}
+\lstset{language=Python}
+\begin{lstlisting}
 var('x,y,z')
 A=matrix([[x,0,1],[y,1,0],[z,0,y]])
 A.det()
 A.inverse()
-\end{verbatim}
+\end{lstlisting}
 \end{frame}
 \begin{frame}
 \frametitle{Summary}
-\label{sec-13}
+\label{sec-12}
 
 \begin{itemize}
-\item We learnt about defining symbolic 
-   expression and functions.
+\item We learnt about defining symbolic expression and functions.
 \item Using built-in constants and functions.
-\item Using <Tab>  to see the documentation of a 
-   function.
-\end{itemize}
-
- 
-\end{frame}
-\begin{frame}
-\frametitle{Summary}
-\label{sec-14}
-
-\begin{itemize}
+\item Using <Tab> to see the documentation of a function.
 \item Simple calculus operations .
-\item Substituting values in expression 
-   using substitute function.
-\item Creating symbolic matrices and 
-   performing operation on them .
+\item Substituting values in expression using substitute function.
+\item Creating symbolic matrices and performing operation on them .
 \end{itemize}
 \end{frame}
 \begin{frame}
 \frametitle{Thank you!}
-\label{sec-15}
+\label{sec-13}
 
   \begin{block}{}
   \begin{center}