I have fixed this for next beta (but testing at the top, not in the loop).
Henry Rich
On 5/6/2022 9:25 PM, Raul Miller wrote:
Hmm...
Ok, so what I think this means is that if we do not want gcd to hang
forever on some arguments we would in effect need to use -.@= in
euclid's algorithm instead of ~:
Or, more specifically, in ve.c
D jtdgcd(J jt,D a,D b){D a1,b1,t;B stop = 0;
a=ABS(a); b=ABS(b); if(a>b){t=a; a=b; b=t;}
ASSERT(inf!=b,EVNAN);
if(!a)R b;
a1=a; b1=b;
while(remdd(a1/jround(a1/a),b1)){t=a; if((a=remdd(a,b))==0)break;
b=t;} // avoid infinite loop if a goes to 0
R a;
} /* D.L. Forkes 1984; E.E. McDonnell 1992 */
we should be testing for _. to avoid an infinite loop.
It might be sufficient to replace if((a=remdd(a,b))==0)break; with
if(!(a=remdd(a,b))!=0)break; (though it's possible that a compiler
might "optimize" that expression and break it).
But, this routine should either return a result or it should throw an error.
--
Raul
On Fri, May 6, 2022 at 7:26 PM Henry Rich <henryhr...@gmail.com> wrote:
Just try adding _. + 4 .
Henry Rich
On 5/6/2022 6:47 PM, Raul Miller wrote:
Huh?
My understanding was that the only acceptable sources of _. were:
direct entry, evaluation, 3!:n and DLL calls.
And, that the only primitives which were allowed to produce results
containing _. were structural primitives which move data without
interpreting it.
--
Raul
On Fri, May 6, 2022 at 5:58 PM Henry Rich <henryhr...@gmail.com> wrote:
No. _. + 4 is not a NaN error. _ - _ is NsN error.
This result should be _. with no error.
Henry Rich
On 5/6/2022 5:55 PM, Raul Miller wrote:
Sure, but that's not prescriptive here.
Here, we have a case where there is no result because _.
(approximately speaking) gives an unhandled infinity as an
unrecognized loop condition.
My gut feeling is that this means that we should treat this as an
example of a case where the result would be _. if we could compute it
(which means that we should throw a NaN error).
Thanks,
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