> From: Uri Guttman > >>>>>>> "BM" == Bob McConnell <r...@cbord.com> writes: >> >> BM> From: Bryan R Harris >>>> >>>> I need to convert a number like this: -3205.0569059 >>>> ... into an 8-byte double (big and little endian), e.g. 4f 3e 52 > 00 2a >> BM> bc 93 >>>> d3 (I just made up those 8 byte values). >>>> >>>> Is this easy in perl? Are long and short ints easy as well? >> >> BM> The sprintf() family is your friend. >> >> that will only generate text (hex and other formats). he needs pack >> which does exactly what he wants. read perlpacktut for a tutorial on >> pack/unpack and then perlfunc -f pack for the reference on it. > > That statement just confuses me. His initial value of -3205.0569059 is > also text. It is the human readable representation of the number, and is > not anything like what it looks like inside the computer. He just asked > for a different format for that text. Why is sprintf not a reasonable > way to do that?
The 8 bytes is an IEEE 754-2008 formatted number -- see here for an explanation: http://en.wikipedia.org/wiki/Double_precision It's not just a simple hex of a decimal... You've got an exponent and a sign encoded in there too. I'm still reading the perlpacktut, but I'm hoping it'll get me to that. - Bryan -- To unsubscribe, e-mail: beginners-unsubscr...@perl.org For additional commands, e-mail: beginners-h...@perl.org http://learn.perl.org/
