import numpy as np

# sample array
data = np.full((3, 4), 4)
data

array([[4, 4, 4, 4],
       [4, 4, 4, 4],
       [4, 4, 4, 4]])

Array dimensions

data.shape #3x4

(3, 4)

Length of array

len(data) # 3 row

3

Number of array dimensions

data.ndim # 2D array

2

Number of array elements

data.size # 3x4 = 12

12

Data type of array elements

data.dtype # return object

dtype('int64')

Name of data type

data.dtype.name # return string

'int64'

Convert an array to different type

data = data.astype(float)
data

array([[4., 4., 4., 4.],
       [4., 4., 4., 4.],
       [4., 4., 4., 4.]])

data.dtype

dtype('float64')