Charles Greathouse on Wed, 23 Oct 2013 23:52:21 +0200 |
[Date Prev] [Date Next] [Thread Prev] [Thread Next] [Date Index] [Thread Index]
Re: parallel pari: parfirst |
Hello PARI developers,
I am experimenting with a new parallel primitive which is a kind of
parapply with early return:
?? parfirst(f, x, {&b}):
Return the smallest index i such that f(x[i]) is non zero, or 0 if none. If
present, b is to f(x[i]).
One example program:
inline(chkell);
chkell(p)=a->my(E=ellinit([1,a],p));isprime(ellcard(E));
ellp(p)=parfirst(chkell(p),[1..10000]);
ellp(p) returns the smallest a>=1 such that the curve y^2=x^3+x+a has prime
order over F_p.
Suggestions for the name and/or the interface ?
The requirement of an explicit vector for x is a bit burdensome, since
we might like x to be unbounded (i.e. infinite).
Cheers,
Bill.