MATLAB: How to convert 4 hex bytes into a single integer

byte conversionbyte readingintegerMATLABtypecase

I'm trying to convert the 4 byte sequence:
in hex:
[3E 29 C3 39]
in dec:
62    41   195    57
Manually converting this into an unsigned long (4-byte) integer (uint32):
A(1)*(256^3) + A(2)*(256^2) + A(3)*256 + A(4)
ans =
                  1042924345
Which is the proper value. However, when I use typecast, I get the wrong value:
>>typecast(A,'int32')
ans =
             0  1078919168           0  1078231040           0  1080582144           0  1078755328
>>typecast(int8(A),'int32')
ans =
     964634942
Am I doing something wrong here? I've using all variations of signed vs. unsigned integer types (both uint8/int8 and uint32/int32) and none of them give the right answer.

Best Answer

Depending on the machine you are on, you may need to use the swapbytes function as well. E.g., try:
swapbytes(typecast(uint8(A),'uint32'))
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