attribute
dtype.
itemsize
The element size of this data-type object.
For 18 of the 21 types this number is fixed by the data-type. For the flexible data-types, this number can be anything.
Examples
>>> arr = np.array([[1, 2], [3, 4]]) >>> arr.dtype dtype('int64') >>> arr.itemsize 8
>>> dt = np.dtype([('name', np.str_, 16), ('grades', np.float64, (2,))]) >>> dt.itemsize 80