plotting_data.rst
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+Plotting   Experimental  Data  
+=============================   
+Hello  and welcome , this tutorial on  Plotting Experimental data is 
+presented by the fossee  team.  
+
+{{{ Show the slide containing title }}}
+
+
+{{{ Show the Outline Slide }}}
+
+Here  we will discuss plotting  Experimental data. 
+
+1.We will see how we can represent a sequence of numbers in Python. 
+
+2.We will also become fimiliar with  elementwise squaring of such a
+sequence. 
+
+3. We will also see how we can use our graph to indicate Error.
+
+One needs   to  be  fimiliar  with  the   concepts  of  plotting
+mathematical functions in Python.
+
+We will use  data from a Simple Pendulum  Experiment to illustrate our
+points. 
+
+{{{ Simple Pendulum data Slide }}} 
+
+  
+  
+  
+As we know for a simple pendulum length,L is directly  proportional to 
+the square of time,T. We shall be plotting L and T^2 values.
+
+
+First  we will have  to initiate L and  T values. We initiate them as sequence 
+of values.  To tell ipython a sequence of values we  write the sequence in 
+comma  seperated values inside two square brackets.  This is also  called List 
+so to create two sequences
+
+L,t type in ipython shell. ::
+
+    In []: L = [0.1, 0.2, 0.3, 0.4, 0.5,0.6, 0.7, 0.8, 0.9]
+    
+    In []: t= [0.69, 0.90, 1.19,1.30, 1.47, 1.58, 1.77, 1.83, 1.94]
+
+
+  
+To obtain the  square of sequence t we will  use the function square
+with argument t.This is saved into the variable tsquare.::
+
+   In []: tsquare=square(t)
+  
+   array([  0.4761, 0.81 , 1.4161,  1.69 , 2.1609,  2.4964, 3.1329, 
+   3.3489, 3.7636])
+
+  
+Now to plot L vs T^2 we will simply type ::
+
+  In []: plot(L,t,.)
+
+'.' here represents to plot use small dots for the point. ::
+
+  In []: clf()
+
+You can also specify 'o' for big dots.::
+ 
+  In []: plot(L,t,o)
+
+  In []: clf()
+
+
+{{{ Slide with Error data included }}}
+
+
+Now we  shall try  and take into  account error  into our plots . The
+Error values for L and T  are on your screen.We shall again intialize
+the sequence values in the same manner as we did for L and t ::
+
+  In []: delta_L= [0.08,0.09,0.07,0.05,0.06,0.00,0.06,0.06,0.01]
+  
+  In []: delta_T= [0.04,0.08,0.11,0.05,0.03,0.03,0.01,0.07,0.01]
+
+
+  
+Now to plot L vs T^2 with an error bar we use the function errorbar()
+
+The syntax of the command is as given on the screen. ::
+
+    
+    In []: errorbar(L,tsquare,xerr=delta_L, yerr=delta_T, fmt='b.')
+
+This gives a  plot with error bar for  x and y axis. The  dots are of
+blue color.
+
+
+similarly we can draw the same error bar with big red dots just change 
+the parameters to fmt to 'ro'. ::
+
+    In []: clf()
+    In []: errorbar(L,tsquare,xerr=delta_L, yerr=delta_T, fmt='ro')
+
+
+
+thats it. you can explore other options to errorbar using the documentation 
+of errorbar.::
+
+   In []: errorbar?
+
+
+{{{ Summary Slides }}}
+
+In this tutorial we have learnt : 
+
+1. How to declare a sequence of number , specifically the kind of sequence we learned was a list.
+
+2. Plotting experimental data extending our knowledge from mathematical functions. 
+
+3. The various options available for plotting dots instead of lines.
+
+4. Plotting experimental data such that we can also represent error. We did this using the errorbar() function.
+
+
+ {{{ Show the "sponsored by FOSSEE" slide }}}
+
+
+
+This tutorial was created as a part of FOSSEE project.
+
+Hope you have enjoyed and found it useful.
+
+ Thankyou
+
+ 
+
+Author              : Amit Sethi
+Internal Reviewer   :
+Internal Reviewer 2 :