How is the data of a numpy.array stored?

Question

This is my simple test code:

data = np.arange(12, dtype='int32').reshape(2,2,3);

so the data is:

array([[[ 0,  1,  2],
    [ 3,  4,  5]],

   [[ 6,  7,  8],
    [ 9, 10, 11]]], dtype=int32)

but why does data.data[:48] look like this:

'\\x00\\x00\\x00\\x00\\x01\\x00\\x00\\x00\\x02\\x00\\x00\\x00\\x03\\x00\\x00\\x00\\x04\\x00\\x00\\x00\\x05\\x00\\x00\\x00\\x06\\x00\\x00\\x00\\x07\\x00\\x00\\x00\\x08\\x00\\x00\\x00\\t\\x00\\x00\\x00\\n\\x00\\x00\\x00\\x0b\\x00\\x00\\x00'

I mean why are '9','10' stored as '\\t\\x00\\x00\\x00' and '\\n\\x00\\x00\\x00'?

Answer 1

\\t is the tab character, of ASCII value 9. \\n is the LF character, of ASCII value 10. \\x00 is a NUL character, of ascii value 0. Thus,

'\\t\\x00\\x00\\x00' represents a sequence of bytes [9, 0, 0, 0], which is a little-endian representation of a long integer 9.

'\\n\\x00\\x00\\x00' represents a sequence of bytes [10, 0, 0, 0], which is a little-endian representation of a long integer 10.