"Scott David Daniels" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] > franzkowiak wrote: >> I've read some bytes from a file and just now I can't interpret 4 bytes >> in this dates like a real value. An extract from my program: >> def l32(c): >> return ord(c[0]) + (ord(c[1])<<8) + (ord(c[2])<<16) + >> (ord(c[3])<<24) >> ... >> value = l32(f.read(4)) <--- 3F 8C CC CD should be 1.11 >> > OK, here's the skinny (I used blocks & views to get the answer): > > import struct > bytes = ''.join(chr(int(txt, 16)) for txt in '3F 8C CC CD'.split()) > struct.unpack('>f', bytes) > > I was suspicious of that first byte, thought it might be an exponent, > since it seemed to have too many on bits in a row to be part of 1.11.
I believe exponents are typically stored as a positive offset from the largest negative exponent. 3F8 is about half of 7FF, so that seems about right for an actual exponent of 0. Terry J. Reedy -- http://mail.python.org/mailman/listinfo/python-list
