pythonarraysnumpyconcatenationtypeerror

Inserting multiple elements into an array in one step


I have an array B with shape (1,7,1). I am trying to insert multiple elements (here, 2 elements) at specific positions in one step. The shape of the new array B3 should be (1,9,1). However, I am getting an error.

import numpy as np

B = np.array([[[0.678731133],
        [1.244425627],
        [0.767884084],
        [2.006154222],
        [3.073758392],
        [1.037728999],
        [5.032947535]]])
B1=np.array([10])
B2=np.array([20])
B3=np.insert(B, 2, B1,8,B2,axis=1)
print("B3=",[B3])
print("B3 shape=",[B3.shape])

The error is

<module>
    B3=np.insert(B, 2, B1,8,B2,axis=1)

  File "<__array_function__ internals>", line 4, in insert

TypeError: _insert_dispatcher() got multiple values for argument 'axis'

The desired output is

B3 = np.array([[[0.678731133],
        [1.244425627],
        [10],
        [0.767884084],
        [2.006154222],
        [3.073758392],
        [1.037728999],
        [5.032947535],
        [20]]])
B3 shape= (1,9,1)

Solution

  • B3=np.insert(B, [2,7],[B1,B2],axis=1) works. You can check np.insert documentation

    print(B3)
    print(B3.shape)
    >>>[[[ 0.67873113]
      [ 1.24442563]
      [10.        ]
      [ 0.76788408]
      [ 2.00615422]
      [ 3.07375839]
      [ 1.037729  ]
      [ 5.03294753]
      [20.        ]]]
    >>>(1, 9, 1)