>>You can always unroll the loop into a single line adding iif(bittest(),1,0) if start and endpoint are fixed....
>>Are you certain optimizing that piece of code is neccessary ?
>>If such a short vfp loop has to be avoided because of using that line/loop/function billions at least, uncertain if vfp's slow function call used for a C-fll would get you faster times than a long vfp-line calling often into the C-runtimes...
>>
>>feels like premature optimization on pure reading ;-)
>
>It's just out of curiosity. Nothing important, just an intellectual problem. I do someting like
>

>?icase(num=0,0,num=3,2,1)
>

>
>on the 2 bit thing and found it boring with bit 2 on.
>
>:)


I think he means


nBIts = iif(bitTest(num, 0), 1, 0) + iif(bitTest(num, 1), 1, 0) + ..... iif(bitTest(num, 31), 1, 0)


Alternatively, you can precompute for 0-255 and put the results in an array

nBits = Array[ 1 + bitand(num, 0xff)] + Array[ 1 + bitand( bitrshift(num, 8), 0xff)] + Array[ 1 + bitand( bitrshift(num, 16), 0xff)]  + Array[ 1 + bitand( bitrshift(num, 24), 0xff)]