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Re: [Bug c/16850] modulo - feature or bug?
For the scientific modulo the integer() function yields the lower
bound integer of the float argument. In C it appears that integer(f)
always equals integer(abs(f)). As a consequence, C modulo's integer
function does not fulfil the equation
integer(f+n) = integer(f) + n
n := any integer
for every f while n!=0. That's bad ground for algebra!
On the bright side, the equation
int(a/b + n) = int(a/b) + n
works fine for all a, b, n where a/b is defined in the
algebraic sense (and note we're talking integers here).
"Computer division" has nothing to do with algebraic
division (well, not very much, anyway). Better get
used to it :-)
Segher