#NumPy之 数组合并和拆分
import numpy as np
#对数组进行变形
a = np.arange(20).reshape((5, 4))
print('(5,4):')
print(a)
a = np.arange(20).reshape((5, -1))
print('(5,-1):')
print(a)
a = np.floor(10 * np.random.random((2, 2, 2)))
print('array a:')
print(a)
b = np.floor(10 * np.random.random((2, 2, 2)))
print('array b:')
print(b)
c = np.vstack((a, b))
print('array c:')
print(c)
#合并数组
a=np.arange(12)
b=np.arange(12)
#沿着一个新的维度（dimension、axis）合并数组，得到一个的数组维度加一
print('stack array:')
print(np.stack((a,b)))
# output:
# [[ 0 1 2 3 4 5 6 7 8 9 10 11]
# [ 0 1 2 3 4 5 6 7 8 9 10 11]]
print(np.stack((a,b),axis=-1))
# output:
# [[ 0 0]
# [ 1 1]
# [ 2 2]
# [ 3 3]
# [ 4 4]
# [ 5 5]
# [ 6 6]
# [ 7 7]
# [ 8 8]
# [ 9 9]
# [10 10]
# [11 11]]
print(np.stack((a,b),axis=1))
# output:
# [[ 0 0]
# [ 1 1]
# [ 2 2]
# [ 3 3]
# [ 4 4]
# [ 5 5]
# [ 6 6]
# [ 7 7]
# [ 8 8]
# [ 9 9]
# [10 10]
# [11 11]]