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For example, if we just want to display the velocity at time instances 0, 1, 2, 3, and 4, we could use the default values
        of the x coordinates: 0, 1, 2, 3, and 4, as shown below in Fig 3.7.
         >>> import matplotlib.pyplot as plt
         >>> velocity = [10, 40, 60, 35, 10]
         >>> plt.plot(velocity, 'r*-.', linewidth = 1.5, markersize = 15, markerfacecolor = 'y',
              markeredgecolor = 'b', markeredgewidth = 1)
         >>> plt.xlabel('Time')
         >>> plt.ylabel('Velocity')
         >>> plt.title('Time vs. Velocity')
         >>> plt.show()





























                                                  Fig 3.7: Time vs. Velocity

        Saving Figure

        Oftentimes, it is necessary to save the graphs for future reference. Indeed, the graphs must be referred by people who
        have nothing to do with the matplotlib library or even programming. The matplotlib library provides the function
        plt.savefig() for saving a graph. Name of the file (including the file format) is provided as the input argument to the
        function plt.savefig(). By default, the figure will be saved in the current working directory. To save the file in some
        other directory, you may specify the complete path name instead of just the file name. For saving the figure in high

        resolution, we can set the optional parameter dpi (dots per inch), by invoking the following statement before plt.
        show():

               plt.savefig('Time vs Velocity.png', dpi = 1000)

               The matplotlib library provides the function plt.savefig() for saving a graph. Name of the file (including the
               file format) is provided as the input argument to the function plt.savefig(). By default, the figure will be saved
               in the current working directory.


        Adding Ticks and Creating Grid


        To enhance the readability of a graph, the plt module allows us to display a rectangular grid using the method plt.
        grid(). The ticks on the x-axis mark the positions of the vertical lines of the grid. The ticks on the y-axis mark the positions
        of the horizontal lines of the grid. The position of ticks is typically described using a sequence (using a list, range(), etc.)
        to method xticks() and yticks(). In the following example, we use x-ticks in steps of 2 and y-ticks in steps of 5.



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