convert signed integer in hex/bin (2's complement) into integer in dec

[ghung]

Hello Folks,

How can I convert a signed integer in hex or bin into integer in dec? hex() seems to treat number as non-signed only.

Many thanks!

Gary





Gary Hung
ASIC Design Engineer

 

[duncdude]

I''m afraid I do not know what a signed integer is - but this might help

print hex 0x1AB

this returns [red]1063[/b]


Kind Regards
Duncan

 

[icrf]

I suggest pack/unpack (the latter for yours needs, but the documentation is better in pack's pod):

http://www.perldoc.com/perl5.8.0/pod/perlpacktut.html

http://www.perldoc.com/perl5.8.0/pod/func/pack.html

http://www.perldoc.com/perl5.8.0/pod/func/unpack.html

________________________________________
Andrew - Perl Monkey

 

[ghung]

Thanks Duncan and Andrew. For example,

dec hex bin
24 18 0001_1000
-24 E8 1110_1000 (2's complement of 0001_1000)

printf( "num in dec : %d \n", hex(18) );
num in dec : 24

printf( "num in dec : %d \n", hex(e8) );
num in dec : 232 (which I actually want to get -24)

I am checking the pack/unpack function now... wish me luck..

Gary


Gary Hung
ASIC Design Engineer

 

[duncdude]

hi ghung

can you give the same example but with decimal 23 and decimal 22

many thanks


Kind Regards
Duncan

 

[icrf]

print unpack('c',pack('H2','e8'));

Pack the hex as hex first (big H means high order nibble first), then unpack it as a signed char, which is a byte.

________________________________________
Andrew - Perl Monkey

 

[ghung]

Thanks Andrew ! it's cool !

Duncan, below is a link about signed integer.

http://www.evergreen.edu/biophysics/technotes/program/2s_comp.htm

Gary Hung
ASIC Design Engineer