This ppt gives idea about plotting codes (graphs) using python language. It consists of different syntax with relevant examples.

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Importing module & plot syntax
Decorating graph
Multiple plotting & Bar graph
4 plots in single Graph
Start
Finish

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Importing Module & Plot Syntax
Plotting means to represent graphically.
Import modules:
1)Numpy
-->import numpy as np
2)Matplotlib
-->import matplotlib.pyplot as plt
Syntax:
x=linspace(start, stop, num)
plot(x,y)
-->x=np.linspace(0, 2*np.pi, 50)
-->plt.plot(x, np.sin(x))

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exercise Decorating Graph
Adding Labels:
xlabel(‘ ‘) & ylabel(‘ ‘)
-->plt.xlabel(‘x’)
-->plt.ylabel(‘sin(x)’)
Giving Tiltle:
title(‘ ‘)
-->plt.title(‘Sinusoidis’)
Plot Function:
plot(x, y, ‘color’, linewidth)
-->plt.plot(x, np.sin(x), ‘r’, linewidth=3)

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Some More Decoration
Adding legend:
legend([‘ ‘] , loc=‘best‘)
-->plt.legend([‘Sin(x)’], loc=‘right’)
Annotating:
annotate(‘title’, xy=(x value, y value))
-->plt.annotate(‘localmax’, xy=(1.5, 1))
Axes Length:
xmin, xmax = xlim( )
ymin, ymax = ylim( )
-->plt.xlim(0, 2*np.pi)
-->plt.ylim(-1, 1)

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Multiple Plotting

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Bar Graph
Code:
import numpy as np
import matplotlib.pyplot as plt
objects = ('Python', 'C++', 'Java', 'Perl', 'Scala', 'Lisp')
y_pos = np.arange(len(objects))
performance = [10, 8, 6, 4, 2, 1]
plt.bar(y_pos, performance, align='center', alpha=0.5)
plt.xticks(y_pos, objects)
plt.xlabel('Objects')
plt.ylabel('Usage')
plt.title('Programming language usage')

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4 plots in Single Graph
Plot x, -x, sin(x), xsin(x), in range -5pie to 5pie
Add a legend, Annotate the origin, Set axis limit to the range of X
Code:
import numpy as np
import matplotlib.pyplot as plt
x= np.linspace(-5*np.pi, 5*np.pi, 500)
plt.plot(x, x, 'b')
plt.plot(x, -x, 'b')
plt.plot(x, np.sin(x), 'g', linewidth=2)
plt.plot(x, x*np.sin(x), 'r', linewidth=3)
plt.xlabel('x axis-->')
plt.ylabel('y axis-->')
plt.legend(['x', '-x', 'sin(x)', 'xsin(x)'])
plt.annotate('origin', xy=(0,0))
plt.xlim(-5*np.pi, 5*np.pi)
plt.ylim(-5*np.pi, 5*np.pi)

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MCQ Question
How will you set X and Y axis limit of a plot so that the region of
the interest is in the rectangle (0,-1.5) (bottom left co-ordinate)
and (2*pi,1.5) (right top co-ordinate)
a) Xlim(0, 2*pi)
Ylim(-1.5, 1.5)
b) Xlim(0, -1.5)
Ylim(2*pi, 1.5)
c) Xlim(2*pi, 0)
Ylim(1.5, -1.5)
d) Xlim(-1.5, 1.5)
Ylim(0, 2*pi)