import numpy as np
a = np.linspace(1, 4, 4)
b = a.reshape(2, 2)
b[0, 0] = 0
print(a[0] + b[0, 0] + b[1, 1])

import numpy as np
a = np.arange(4)
b = a.transpose()
x = a.shape == b.shape
print(x)

import numpy as np
a = np.array([1, 2])
b = np.array([3, 4])
c = np.hstack((a, b))
print(c.shape)

import numpy as np
a = np.array([1, 2])
b = np.array([3, 4])
c = np.vstack((a, b))
print(c.shape)

import numpy as np
a = np.array([1, 2])
b = np.array([3, 4])
c = np.dstack((a, b))
print(c.shape)

import numpy as np 
a = np.arange(4)
x = np.hsplit(a, 2)[0]
print(x.sum())

import numpy as np
a = np.arange(6)
a = a.reshape(-1, 1)
x = np.vsplit(a, 2)[-1].sum()
print(x)

import numpy as np
a = np.arange(8).reshape((2, 2, 2))
x = np.dsplit(a, 2)[0].sum()
print(x)

import numpy as np
a = np.array([1, 2, 3, 4, 5])
b = a[[0, 1, 2]]
c = a[0:3]
b[0] = -1
c[1] = -1
print(a[0], a[1])