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Given the following text description, write Python code to implement the functionality described below step by step
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Description:
 PyEarthScience
Step1:  Show the plot inside notebook.
Step2:  Create x- and y-values.
Step3:  Draw data, set title and axis labels.
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Python Code:
#-- load python packages
import numpy as np
from matplotlib import pyplot as plt
Explanation: PyEarthScience:  Python examples for Earth Scientists
XY-plots
Using matplotlib
Line plot with
- marker
- different colors
- legend
- title
- x-axis label
- y-axis label
End of explanation
%matplotlib inline
Explanation: Show the plot inside notebook.
End of explanation
#-- create x-values
x1 = np.arange(0,8,1)
x2 = np.arange(100)
#-- create y-values
data   = np.arange(1,40,5)
linear = np.arange(100)
square = [v * v for v in np.arange(0,10,0.1)]
Explanation: Create x- and y-values.
End of explanation
plt.plot(x1, data,   "ob")         # marker o=open circle, b=black
plt.plot(x2, linear, "g")          # no marker, g=green
plt.plot(x2, square, "+r")         # marker +=cross, r=red
plt.legend(('data','linear','square'), loc='upper left')
plt.title('Title string')
plt.xlabel('x-axis label')
plt.ylabel('y-axis label')
plt.show()
Explanation: Draw data, set title and axis labels.
End of explanation
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