Re: [PD] weird float/add limitation

Le 28/01/2015 17:47, Alexandre Torres Porres a écrit :

...

it's a limitation of 32 bit float

I thought so, but same happens when I use the new Pd Vanilla 64 bits...

this mean that it's compiled for 64 bit CPU, not that float are store on 64 bits

you can have 8 bit int, 32 bit float and 64 bit float (and more) on a 32 bit CPU. and also on a 64 bit CPU. even 8 bit cpu can deal with 32/64 bit float...

cheers c

what now? :)

2015-01-28 14:41 GMT-02:00 Cyrille Henry <ch@chnry.net mailto:ch@chnry.net>:

Le 28/01/2015 17:20, Alexandre Torres Porres a écrit :

    howdy, check the attached patch.

    1e+06 + 1 is not equal to 1e+06

    but 1e+09 + 1 is equal to 1e+09

    meaning it didn't add 1 to 1e+09! Meaning there's a limit where it stops adding 1 to something.

    how's that and why?


it's a limitation of 32 bit float.
since 1 bit is used for the sign, 8 for the exponent, 23 bit are left for the significant.
this mean that you can't have more precision in the significant than 2^24 -1 (a bit less than 1.7*10^7)

cheers
c


    cheers


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