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Time Narration
00:00 Hello and welcome to the tutorial on "Saving plots".
00:04 At the end of this tutorial, you will be able to-

Save plots using savefig() function. Save plots in different formats.

00:13 Before beginning this tutorial, we would suggest you to complete the tutorial on "Using plot interactively".
00:19 Now, start your IPython interpreter with the command ipython hyphen pylab.
00:30 As you know, it will start your IPython interpreter with the required python modules for plotting and saving your plots.
00:36 To start with, let us plot a sine wave from minus 3 pi to 3 pi.
00:43 Let us start by calculating the required points for the plot.
00:45 It can be done using linspace as-
00:51 You can type: x = linspace within brackets minus 3 into pi comma 3 into pi comma 100.
00:59 We have stored the required points in 'x'.
01:03 Now, let us plot the points using the 'plot' statement. So, type: plot (x, sinx).
01:18 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.
01:32 So, saving the plot, we will use savefig() function.
01:36 For this, we shall keep the plot window open alongside the terminal.
01:40 The statement is: savefig within brackets in single quotes slash home slash fossee slash sine dot png.
01:52 Notice that savefig() function takes one argument which is the filename. The last 3 characters after the '.' in the filename, is the extension and type of the file which determines the format in which you want to save.
02:10 Also, note that we gave the full path or the absolute path to which we want to save the file.
02:18 Here, we have used an extension dot png which means we want to save the image as a PNG file.
02:25 Now, let us locate the file sine dot png which we had saved a while ago.
02:32 We have saved the file to slash home slash fossee. So, let us navigate to slash home slash fossee using the file browser.
02:49 Yes, the file sine dot png is here.
02:52 Let us open it and check.
02:57 So, in-order to save a plot, we use savefig() function.
03:05 dot 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.

03:24 Pause the video here, try out the following exercise and resume the video.
03:29 Save the sine plot in the EPS format which can be embedded in LaTeX documents.
03:37 We still have the sine plot with us, let us now save the plot as sine dot eps.
03:49 Now, we will save the plot using the function savefig(). So, you can type: savefig within brackets in single quotes slash home slash fossee slash sine dot eps and hit Enter.
04:04 Now, let us go to: slash home slash fossee and see the new file created.
04:13 Yes! the new file sine dot eps is here.
04:18 Pause the video here, try out the following exercise and resume the video.
04:23 Save the sine plot in PDF, PS and SVG formats.
04:31 This brings us to the end of this tutorial.
04:34 In this tutorial, we have learnt to save plots using the savefig() function.
04:38 Then save the plots in different formats like - pdf, ps, png, svg, eps.
04:45 Here are some self assessment questions for you to solve-
04:48 1. Which command is used to save a plot. saveplot(), savefig(), savefigure(), saveplt()?
04:59 2. savefig('sine.png') saves the plot in-
05:04 The root directory (on GNU/Linux, Unix based systems)- c colon slash (on windows).
05:14 The second option- Will result in an error as full path is not supplied.
05:18 The third one- The current working directory.
05:21 and final option is- Predefined directory like "/documents".
05:26 And now, the answers-
05:28 1. To save a plot, we use the savefig() function.
05:33 2. Whenever we save a file, it gets saved in the current working directory.
05:38 Hope you have enjoyed and found it useful. Thanks.

Contributors and Content Editors

Gaurav, Jyotisolanki, Minal, PoojaMoolya, Sandhya.np14, Sneha