我有一个numpy_array。比如[a b c]。
然后我想将它与另一个NumPy数组连接起来(就像我们创建列表的列表一样)。如何创建包含NumPy数组的NumPy数组?
我试着做下面的事情,但没有任何运气
>>> M = np.array([])
>>> M
array([], dtype=float64)
>>> M.append(a,axis=0)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AttributeError: 'numpy.ndarray' object has no attribute 'append'
>>> a
array([1, 2, 3])
如果我明白你的问题,我有一个办法。假设你有:
a = [4.1, 6.21, 1.0]
这里有一些代码…
def array_in_array(scalarlist):
return [(x,) for x in scalarlist]
这就导致:
In [72]: a = [4.1, 6.21, 1.0]
In [73]: a
Out[73]: [4.1, 6.21, 1.0]
In [74]: def array_in_array(scalarlist):
....: return [(x,) for x in scalarlist]
....:
In [75]: b = array_in_array(a)
In [76]: b
Out[76]: [(4.1,), (6.21,), (1.0,)]
In [1]: import numpy as np
In [2]: a = np.array([[1, 2, 3], [4, 5, 6]])
In [3]: b = np.array([[9, 8, 7], [6, 5, 4]])
In [4]: np.concatenate((a, b))
Out[4]:
array([[1, 2, 3],
[4, 5, 6],
[9, 8, 7],
[6, 5, 4]])
或:
In [1]: a = np.array([1, 2, 3])
In [2]: b = np.array([4, 5, 6])
In [3]: np.vstack((a, b))
Out[3]:
array([[1, 2, 3],
[4, 5, 6]])