On 10/11/2025 03:52, Kenneth wrote:
> In any case, POV-ray's 'mod' can obviously work with float values too...and
> fractions...at least when running in Windows. So IMO the docs are either
> outdated or too 'strict', and at least somewhat unclear.

Indeed, the definition given in the documentation is somewhat 
restrictive or ambiguous at first glance.

Just as multiplication is a simple addition, division is a simple 
subtraction.

Starting with any number (numerator), subtract the denominator as many 
times as possible : that is, as long as the remainder is greater than 
the denominator.

The “last” number is therefore the remainder. This is the number that 
the modulo function returns.


Try this :

#declare a = 27.44;
#declare b = 7.97;

#while(a > b)
  #declare r = a - b;
  #debug concat("mod(",str(a,0,2),", ",str(b,0,2),") = ",str(r,0,2),"\n")
  #declare a = r;
#end



Which gives :

mod(27.44, 7.97) = 19.47
mod(19.47, 7.97) = 11.50
mod(11.50, 7.97) = 3.53



...and 3.53 is of course equal to mod(27.44, 7.97)




-- 
kurtz le pirate
compagnie de la banquise

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