Python-3.4.3/C2/Plotting-Data/English

Python/C2/Plotting data /English Title of script: Plotting data

Author: Aditya Palaparthy

Keywords: Python, IPython, plot, title, errorbar

Visual Cue	Narration
Show Slide containing title, name of the production team along with the logo of MHRD	Hello Friends. Welcome to the tutorial on "Plotting data ".
Show Slide Objectives	In this tutorial, we will learn about Define a list of numbers. Perform element-wise squaring of the list. Plot data points. Plot errorbars.
System Requirements Ubuntu Linux 14.04	To record this tutorial, I am using Ubuntu Linux 14.04 operating system Python 3.4.3 IPython 5.1.0
Show Slide Pre-requisites	To practise this tutorial, you should know how to run basic Python commands on the ipython console use Plots interactively Embellish a plot If not, see the relevant Python tutorials on this website.
[Terminal] ipython3	Let us first open the Terminal by pressing Ctrl+Alt+T keys simultaneously. Now, type ipython3 and press Enter.
[IPython console] %pylab and press Enter.	Let us initialise the pylab package. Type %pylab and press Enter.
Show Slide Example - Simple Pendulum	Let us see an example for plotting the data related to a Simple Pendulum. For a simple pendulum L is directly proportional to the square of time T. We will be plotting L and T^2 values.
Show slide Simple Pendulum Data	Let us use the data shown here for plotting.
[Ipython Terminal] l = [0.1, 0.2, 0.3, 0.4, 0.5,0.6, 0.7, 0.8, 0.9] t= [0.69, 0.90, 1.19,1.30, 1.47, 1.58, 1.77, 1.83, 1.94]	First let us initiate 'l' and 't' values. We initiate them as sequence of values. This is also called as List. Type l equal to within square brackets values and press Enter t equal to within square brackets the values and press Enter
[Ipython Terminal] tsquare=square(t)	Now we will obtain square of t by using function square. Type tsquare=square within parentheses t and press Enter
tsquare	Now type tsquare and press Enter
show array in terminal array([ 0.4761, 0.81 , 1.4161, 1.69 , 2.1609, 2.4964, 3.1329, 3.3489, 3.7636])	We see the values of tsquare
[Ipython Terminal] plot(l,tsquare,'.')	Now to plot L v/s T^2, we will simply type plot within parentheses I comma tsquare comma within single quotes dot and press Enter
Show the plot window	We see the required plot.
[Ipython Terminal] clf()	You can also specify 'o' for filled circles. For this let us clear the plot first. Type clf parentheses Enter
Show plot window	So the plot is clear now
plot(l,tsquare,'o')	Now type, plot within parentheses I comma tsquare comma within single quotes o and press Enter
Show plot window	We see the plot with filled circles
Show Slide Exercise 1	Pause the video. Try this exercise and then resume the video Plot the given experimental data with large dots. The data is on your screen.
Show Slide Exercise 1 data	Use the error data given here for plotting.
[Ipython Terminal] delta_l= [0.08,0.09,0.07,0.05,0.06,0.00,0.06,0.06,0.01] delta_t= [0.04,0.08,0.03,0.05,0.03,0.03,0.04,0.07,0.08]	We shall again initialize the sequence values in the same manner as we did for l and t. Type delta_l within square bracket the values and press Enter delta_t within square bracket the values and press Enter
[Ipython Terminal] errorbar(l,tsquare,xerr=delta_l, yerr=delta_t, fmt='bo')	Now to plot L versus T^2 with an error bar, we use the function errorbar(). So type, errorbar within parentheses I comma tsquare comma xerr equalto delta_I comma y_err equalto delta_t comma fmt= within single quotes bo and press Enter
Show plot window	We see plot L versus T^2 with an error bar
[Ipython Terminal] errorbar?	You can explore other options of errorbar using the documentation of errorbar. That is, errorbar question mark
Show Slide Exercise 2	Pause the video. Try this exercise and then resume the video. Plot the given experimental data with small dots. Also include the error in your plot.
Show Slide Exercise 2 data	Use the data given here for plotting.
Show Slide Summary slide	This brings us to the end of this tutorial. In this tutorial, we have learned to, Declare a list of numbers using the function array. Perform element-wise squaring using the square function. Use the various options available for plotting like dots, lines. Plot experimental data such that we can also represent error by using the errorbar() function.
Show Slide Evaluation	Here are some self assessment questions for you to solve. Square the following sequence.distance_values equalto within square brackets 2.1,4.6,8.72,9.03 Plot L versus T in red pluses.
Show Slide Solutions	And the answers, 1.To square a sequence of values, we use the function square square within parentheses distance_values 2. We pass an additional argument stating the desired parameter plot within parentheses L comma T comma within single quotes r plus for red pluses
Show Slide Forum	Please post your timed queries in this forum.
Show Slide Fossee Forum	Please post your general queries on Python in this forum.
Show Slide Textbook Companion	FOSSEE team coordinates the TBC project.
Show Slide Acknowledgement	Spoken-tutorial is funded by NMEICT, MHRD, Govt. of India. For more details, visit this website.
Show Slide Thank You	This is _________ from IIT Bombay signing off. Thank You

Contributors and Content Editors

Nancyvarkey, Nirmala Venkat, Pratham920