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jacobian

the Jacobian of a list of polynomials

Syntax
jacobian(L: LIST of RINGELEM): MAT
jacobian(L: LIST of RINGELEM, X: LIST of indets): MAT

Description
This function returns the Jacobian matrix of the polynomials in the non empty list L with respect to all the indeterminates of the ring of L or, if specified, to the indeterminates in X .

Example
/**/  use R ::= QQ[x,y];
/**/  L := [x-y, x^2-y, x^3-y^2];
/**/  jacobian(L);
matrix( /*RingWithID(26, "QQ[x,y]")*/
 [[1, -1],
  [2*x, -1],
  [3*x^2, -2*y]])
/**/  jacobian(L,[y]);
matrix( /*RingWithID(26, "QQ[x,y]")*/
 [[-1],
  [-1],
  [-2*y]])