Floor and ceiling and eq in j all uses comparison tolerance, So when the
result is set to 0 if floor and ceiling are equal in the J sense, we get
the zero result. The question s then if this is the correct behaviour.
As we can see floor uses comparison tolerance. It is not obvious to me
why. It is not a comparison. If it didn't, we would get the correct result.
Another possibility is to use comparison tolerance = 0 for floor and
ceiling only here, if that would be what we consider correct behaviour.
q=: 5729082486784839 % 196
30j5":q
29230012687677.75000
30j5":<.q
29230012687678.00000
30j5":>.q
29230012687678.00000
30j5":(>.q) = <.q
1.00000
9!:19]0
30j5":q
29230012687677.75000
30j5":<.q
29230012687677.00000
30j5":>.q
29230012687678.00000
30j5":(>.q) = <.q
0.00000
Cheers,
Erling
Den 2017-09-13 kl. 16:34, skrev Raul Miller:
Hmm... actually... no...
The relevant implementation here is in ve.c:
static D jtremdd(J jt,D a,D b){D q,x,y;
if(!a)R b;
ASSERT(!INF(b),EVNAN);
if(a==inf )R 0<=b?b:a;
if(a==infm)R 0>=b?b:a;
q=b/a; x=tfloor(q); y=tceil(q); R teq(x,y)?0:b-a*x;
}
No hint of fmod here (though it does get used elsewhere).
FYI,
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