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| -rw-r--r-- | saving_plots/script.rst | 194 |
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diff --git a/saving_plots/script.rst b/saving_plots/script.rst index 1134d48..7019015 100644 --- a/saving_plots/script.rst +++ b/saving_plots/script.rst @@ -25,86 +25,131 @@ ======= Savefig ======= +.. L1 -{{{ Show the first slide }}} +{{{ Show the first slide containing title, name of the production +team along with the logo of MHRD }}} -Hello and welcome to the tutorial saving plots. +.. R1 -{{{ switch to next slide, outline slide }}} +Hello and welcome to the tutorial on "saving plots". -In this tutorial you will learn how to save plots using Python, saving -in different formats, and locating the file in the file system. +.. L2 -.. #[Puneeth: file-system is too technical.] +{{{ Show slide with objectives }}} + +.. R2 + +At the end of this tutorial, you will be able to, + + 1. Save plots using ``savefig()`` function. + #. Save plots in different formats. + +.. L3 {{{ switch to next slide, a sine wave}}} -Start your IPython interpreter with the command :: +.. R3 + +Start your IPython interpreter with the command +ipython -pylab + +.. L4 + +:: - ipython -pylab + ipython -pylab + +.. R4 As you know, it will start your IPython interpreter with the required python modules for plotting and saving your plots. -{{{ Open ipython }}} +To start with let us plot a sine wave from minus 3 pi to 3 pi. +Let us start by calculating the required points for the plot. It +can be done using linspace as, + +.. L5 + +:: + + x = linspace(-3*pi,3*pi,100) -Now let us plot something, let us plot a sine wave from minus 3 pi to -3 pi. Let us start by calculating the required points for the plot. It -can be done using linspace as, :: +.. R5 - x = linspace(-3*pi,3*pi,100) +We have stored the required points in x. Now let us plot the points using +the plot statement. -We have stored required points in x. Now let us plot the points using -the statement :: +.. L6 - plot(x,sin(x)) +:: + + plot(x,sin(x)) {{{ Keep the plot open }}} +.. R6 + Done! we have made a very basic sine plot, now let us see how to save the plot for future use so that you can embed the plot in your reports. -.. #[Puneeth: All this is known stuff. You don't have to elaborate so -.. much on it. Just say, let us plot sin function from -3 pi to 3 -.. pi. Show the commands, and be done with it. ] +.. L7 {{{ switch to next slide, savefig() }}} {{{ Switch the focus to IPython interpreter window }}} -For saving the plot, we will use ``savefig()`` function, and it has to be -done with the plot window open. The statement is, :: +.. R7 + +For saving the plot, we will use ``savefig()`` function.For this we shall keep the +plot window open alongside the terminal. The statement is, - savefig('/home/fossee/sine.png') +.. L8 + +:: + + savefig('/home/fossee/sine.png') + +.. R8 Notice that ``savefig`` function takes one argument which is the filename. The last 3 characters after the ``.`` in the filename is the extension or type of the file which determines the format in which you want to save. -.. #[Puneeth: removed mention of string] - -.. #[[Anoop: I think this treatment is better :) ]] +.. L9 {{{ Highlight the /home/fossee part using mouse movements }}} +.. R9 + Also, note that we gave the full path or the absolute path to which we want to save the file. +.. L10 + {{{ Highlight the .png part using mouse movements }}} -Here I have used an extension ``.png`` which means I want to save the +.. R10 + +Here we have used an extension ``.png`` which means we want to save the image as a PNG file. -Now let us locate ``sine.png`` file saved. We saved the file to +Now let us locate the file ``sine.png`` which we had saved a while ago.We saved the file to ``/home/fossee`` so let us navigate to ``/home/fossee`` using the file browser. +.. L11 + {{{ Open the browser, navigate to /home/fossee and highlight the file sine.png }}} -Yes, the file ``sine.png`` is here and let us check it. +.. R11 + +Yes, the file ``sine.png`` is here.let us open it and check. + +.. L12 {{{ Open the file sine.png and show it for two-three seconds and then close it and return to IPython interpreter, make sure the plot window @@ -112,52 +157,131 @@ is still open, also don't close the file browser window }}} {{{ switch to next slide, More on savefig() }}} +.. R12 + So in-order to save a plot, we use ``savefig`` function. ``savefig`` can save the plot in many formats, such as pdf - portable document format, ps - post script, eps - encapsulated post script, svg - scalable vector graphics, png - portable network graphics which support transparency etc. -.. #[[slide must give the extensions for the files - Anoop]] +.. L13 {{{ switch to next slide, exercise 1 }}} +.. R13 + Let us now try to save the plot in eps format. ``eps`` stands for encapsulated post script, and it can be embedded in your latex documents. Pause here and try to figure it out yourself. +.. L14 + {{{ Switch focus to the already open plot window }}} +.. R14 + We still have the sine plot with us, and now let us save the plot as ``sine.eps``. +.. L15 + {{{ switch to next slide, solution 1 }}} {{{ Switch focus to IPython interpreter }}} -Now, We will save the plot using the function ``savefig`` :: +.. R15 + +Now, We will save the plot using the function ``savefig`` + +.. L16 + +:: - savefig('/home/fossee/sine.eps') + savefig('/home/fossee/sine.eps') {{{ Switch focus to file browser window }}} +.. R16 + Now let us go to ``/home/fossee`` and see the new file created. +.. L17 + {{{ Highlight the file sine.eps with a single mouse click for 2 seconds and then double click and open the file }}} +.. R17 + Yes! the new file ``sine.eps`` is here. +.. L18 + {{{ switch to next slide, exercise 2 }}} +.. R18 + Now you may try saving the same in pdf, ps, svg formats. +.. L19 + {{{ Switch to summary slide }}} -This brings us to the end of this tutorial, in this tutorial we -learned to save plots using the function ``savefig()``. Saving the -plots in different formats and locating the files in the file system. +.. R19 + +This brings us to the end of this tutorial, +let's revise quickly what we have learnt today + + 1. to save plots using the ``savefig()`` function. + #. to save the plots in differnt formats. + - pdf + - ps + - png + - svg + - epg + #. to locate files in the file system. + +.. R20 + +Here are some self assessment questions for you to solve + +1. Which command is used to save a plot. + + - saveplot() + - savefig() + - savefigure() + - saveplt() + + +2. ``savefig('sine.png')`` saves the plot in, + + - The root directory ``/`` (on GNU/Linux, Unix based systems) + ``c:\`` (on windows). + - Will result in an error as full path is not supplied. + - The current working directory. + - Predefined directory like ``/documents``. + +.. L20 + +{{Show self assessment questions slide}} + +.. L21 + +(solution of self assessment questions on slide) + +.. R21 + +And the answers, + +1.To save a plot,we use the ``savefig()`` function. + +2.Whenever we save a file,it gets saved in the current working directory. + +.. L22 + +{{{ a thank you slide }}} -{{{ switch to Thank you slide }}} +.. R22 +Hope you have enjoyed and found it useful. Thank you! |