Home Online Manual
Top
Back: multRat
Forward: commRing
FastBack: ratgb_lib
FastForward: Examples
Up: dmodloc_lib
Top: Singular Manual
Contents: Table of Contents
Index: Index
About: About this document
7.7.21.0. diffRat
Procedure from library dmodloc.lib (see dmodloc_lib).

Usage:
diffRat(v,j); v vector, j int

Assume:
Assume that v has exactly two components, second one not 0.

Return:
vector, representing rational function derivative of rational function (v[1]/v[2]) w.r.t. var(j)

Note:
Possibly present non-commutative relations of the basering are ignored.

Example:
 
LIB "dmodloc.lib";
ring r = 0,(x,y),dp;
vector v = [x,y];
diffRat(v,1);
==> y*gen(2)+gen(1)
diffRat(v,1) - [1,y];
==> 0
diffRat(v,2);
==> y2*gen(2)-x*gen(1)
diffRat(v,2) - [-x,y2];
==> 0