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+Hello friends. Welcome to this spoken tutorial on Multiple plots.
+
+{{{ Show the slide containing the title }}}
+
+{{{ Show the slide containing the outline }}}
+
+In this tutorial, we will learn how to draw more than one plot, how to
+add legends to each plot to indicate what each plot represents. We
+will also learn how to switch between the plots and creating multiple
+plots with different regular axes which are also called as subplots.
+
+{{{ Shift to terminal and start ipython -pylab }}}
+
+To begin with let us start ipython with pylab, by typing::
+
+  ipython -pylab
+
+on the terminal
+
+Let us first create set of points for our plot. For this we will use
+the command called linspace::
+
+  x = linspace(0, 50, 10)
+
+linspace command creates 10 points in the interval between 0 and 50
+both inclusive. We assign these values to a variable called x.
+
+Now let us draw a plot simple sine plot using these points::
+
+  plot(x, sin(x))
+
+This should give us a nice sine plot.
+
+{{{ Switch to the plot window }}}
+
+Oh! wait! Is that a nice sine plot? Does a sine plot actually look
+like that? We know that a sine plot is a smooth curve is it not? What
+really caused this?
+
+{{{ pause for a while }}}
+
+A small investigation on linspace tells us that we chose too few
+points in a large interval between 0 and 50 for the curve to be
+smooth. So now let us use linspace again to get 500 points between 0
+and 100 and draw the sine plot
+
+{{{ Switch to ipython andtype }}} ::
+
+  y = linspace(0, 50, 500)
+  plot(y, sin(y))
+
+{{{ Change to the plot window }}}
+
+Now we see what we remember as a sine plot. A smooth curve. If we
+carefully notice we also have two plots now one overlaid upon
+another. In pylab, by default all the plots are overlaid.
+
+We now know how to draw multiple plots but we would like to have more
+control over it. Like switch between them, perform some operations or
+labelling on them individually and so on. Let us see how to accomplish
+this. Before we move on, let us clear our screen.
+
+{{{ Switch to ipython }}}::
+
+  clf()
+
+To accomplishing more control over individual plots we use the figure
+command::
+
+  x = linspace(0, 50, 500)
+  figure(1)
+  plot(x, sin(x), 'b')
+  figure(2)
+  plot(x, cos(x), 'g')
+
+{{{ Switch to plot window }}}
+
+Now we have two plots, a sine plot and a cosine plot one overlaid upon
+the other.
+
+{{{ Have both plot window and ipython side by side }}}
+
+The figure command takes an integer as an argument which is the serial
+number of the plot. This selects the corresponding plot. All the plot
+commands we run after this are applied to the selected plot. In this
+example figure 1 is the sine plot and figure 2 is the cosine plot. We
+can, for example, save each plot separately
+
+{{{ Switch to ipython }}}::
+
+  savefig('/home/user/cosine.png')
+  figure(1)
+  title('sin(y)')
+  savefig('/home/user/sine.png')
+
+{{{ Have both plot window and ipython side by side }}}
+
+We also titled the our first plot as 'sin(y)' which we did not do for
+the second plot.
+
+Since we have two plots now overlaid upon each other we would like to
+have a way to indicate what each plot represents to distinguish
+between them. This is accomplished using legends. Equivalently, the
+legend command does this for us
+
+{{{ Switch to ipython }}}::
+
+  legend(['sin(x)', 'cos(x)'])
+
+The legend command takes a single list of parameters where each
+parameter is the text indicating the plots in the order of their
+serial number.
+
+{{{ Switch to plot window }}}
+
+Now we can see the legends being displayed for the respective sine and
+cosine plots on the plot area.
+
+At times we run into situations where we want to compare two plots and
+in such cases we want to draw both the plots in the same plotting
+area. The situation is such that the two plots have different regular
+axes which means we cannot draw overlaid plots. In such cases we can
+draw subplots.
+
+We use subplot command to accomplish this
+
+{{{ Switch to ipython }}}::
+
+  subplot(2, 1, 1)
+
+subplot command takes three arguments, the first being the number of
+rows of subplots that must be created,
+
+{{{ Have both plot window and ipython side by side }}}
+
+in this case we have 2 so it spilts the plotting area horizontally for
+two subplots. The second argument specifies the number of coloumns of
+subplots that must be created. We passed 1 as the argument so the
+plotting area won't be split horizontally and the last argument
+specifies what subplot must be created now in the order of the serial
+number. In this case we passed 1 as the argument, so the first subplot
+that is top half is created. If we execute the subplot command as
+
+{{{ Switch to ipython }}}::
+
+  subplot(2, 1, 2)
+
+{{{ Switch to plot window }}}
+
+The lower subplot is created. Now we can draw plots in each of the
+subplot area using the plot command.
+
+{{{ Switch to ipython }}}::
+
+  x = linspace(0, 50, 500)
+  plot(x, cos(x))
+  subplot(2, 1, 1)
+  y = linspace(0, 5, 100)
+  plot(y, y ** 2)
+
+{{{ Have both plot window and ipython side by side }}}
+
+This created two plots one in each of the subplot area. The top
+subplot holds a parabola and the bottom subplot holds a cosine
+curve.
+
+As seen here we can use subplot command to switch between the subplot
+as well, but we have to use the same arguments as we used to create
+that subplot, otherwise the previous subplot at that place will be
+automatically erased. It is clear from the two subplots that both have
+different regular axes. For the cosine plot x-axis varies from 0 to
+100 and y-axis varies from 0 to 1 where as for the parabolic plot the
+x-axis varies from 0 to 10 and y-axis varies from 0 to 100
+
+{{{ Show summary slide }}}
+
+This brings us to the end of another session. In this tutorial session
+we learnt
+
+ * How to draw multiple plots which are overlaid
+ * the figure command
+ * how to switch between the plots and perform some operations on each
+   of them like saving the plots
+ * the legend command and
+ * creating and switching between subplots
+
+{{{ Show the "sponsored by FOSSEE" slide }}}
+
+This tutorial was created as a part of FOSSEE project, NME ICT, MHRD India
+
+Hope you have enjoyed and found it useful.
+Thankyou
+ 
+.. Author              : Madhu
+   Internal Reviewer 1 :         [potential reviewer: Puneeth]
+   Internal Reviewer 2 :         [potential reviewer: Nishanth]
+   External Reviewer   :
+