convert binary string to numpy array

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Assume I have the string:

my_data = '\x00\x00\x80?\x00\x00\x00@\x00\x00@@\x00\x00\x80@'

Where I got it is irrelevant, but for the sake of having something concrete, assume I read it from a binary file.

I know my string is the binary representation of 4 (4-byte) floats. I would like to get those floats as a numpy array. I could do:

import struct
import numpy as np
tple = struct.unpack( '4f', my_data )
my_array = np.array( tple, dtype=np.float32 )

But it seems silly to create an intermediate tuple. Is there a way to do this operation without creating an intermediate tuple?

EDIT

I would also like to be able to construct the array in such a way that I can specify the endianness of the string.

binary-data numpy python
2 Answers

np.fromstring() is deprecated. Use np.frombuffer() instead.

import numpy as np

my_data = b'\x00\x00\x80?\x00\x00\x00@\x00\x00@@\x00\x00\x80@'

# np.fromstring is deprecated
# data = np.fromstring(my_data, np.float32)
data = np.frombuffer(my_data, np.float32)

print(data)

[1. 2. 3. 4.]
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