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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:
 Numpy Exercise 1
Imports
Step1:  Checkerboard
Write a Python function that creates a square (size,size) 2d Numpy array with the values 0.0 and 1.0
Step2:  Use vizarray to visualize a checkerboard of size=20 with a block size of 10px.
Step3:  Use vizarray to visualize a checkerboard of size=27 with a block size of 5px.
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Python Code:
import numpy as np
%matplotlib inline
import matplotlib.pyplot as plt
import seaborn as sns
import antipackage
import github.ellisonbg.misc.vizarray as va
Explanation: Numpy Exercise 1
Imports
End of explanation
def checkerboard(size):
    Z = np.empty((size,size),dtype=float)
    Z.fill(1.0)
    Z[1::2,::2] = 0.0
    Z[::2,1::2] = 0.0
    return Z
va.vizarray(Z)
checkerboard(4)
a = checkerboard(4)
assert a[0,0]==1.0
assert a.sum()==8.0
assert a.dtype==np.dtype(float)
assert np.all(a[0,0:5:2]==1.0)
assert np.all(a[1,0:5:2]==0.0)
b = checkerboard(5)
assert b[0,0]==1.0
assert b.sum()==13.0
assert np.all(b.ravel()[0:26:2]==1.0)
assert np.all(b.ravel()[1:25:2]==0.0)
Explanation: Checkerboard
Write a Python function that creates a square (size,size) 2d Numpy array with the values 0.0 and 1.0:
Your function should work for both odd and even size.
The 0,0 element should be 1.0.
The dtype should be float.
End of explanation
va.enable()
va.set_block_size(10)
checkerboard(20)
assert True
Explanation: Use vizarray to visualize a checkerboard of size=20 with a block size of 10px.
End of explanation
va.set_block_size(5)
checkerboard(27)
assert True
Explanation: Use vizarray to visualize a checkerboard of size=27 with a block size of 5px.
End of explanation
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