|
|
7.5.15.0. isInvertibleNcfrac
Procedure from library ncfrac.lib (see ncfrac_lib).
- Usage:
- isInvertibleNcfrac(frac), ncfrac frac
- Purpose:
- checks if frac is invertible
- Return:
- int, 1 if frac is invertible, 0 otherwise
Example:
| | LIB "ncfrac.lib";
==> // ** redefining testNcfrac (LIB "ncfrac.lib";) ./examples/isInvertibleNc\
frac.sing:1
==> // ** redefining testNcloc ( LIB "ncloc.lib";) ncfrac.lib::mod_init:11\
3
ring R = 0,(x,y,Dx,Dy),dp;
def S = Weyl();
setring S;
ncloc loc = intvec(2);
ncfrac frac = list([y,y+1,0,0], loc);
isInvertibleNcfrac(frac);
==> 1
frac = list([y,x+1,0,0], loc);
isInvertibleNcfrac(frac);
==> 0
|
|
