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D.15.2.32 derivationFromPoly

Procedure from library difform.lib (see difform_lib).

Usage:
derivation phi = derivationFromPoly(f); f poly

Return:
a derivation which maps any degree-1 generator to f

Remarks:
The degree-1 generators are returned by diffAlgebraListGen

Note:
the procedure allows to interpret polynomials as derivations

Example:
 
LIB "difform.lib";
ring R = 0,(x,y,z),lp;
diffAlgebra();
==> // The differential algebra Omega_R was constructed and the differential \
   forms dDx, dDy, dDz, dx, dy, dz are available.
//////////////////////////////////////////////////
// Construction of derivations from polynomials //
//////////////////////////////////////////////////
derivation phi = derivationFromPoly(3x*y - 12*y4-z2); phi;
==>  Omega_R^1 --> R
==>        dx |--> 3xy-12y4-z2
==>        dy |--> 3xy-12y4-z2
==>        dz |--> 3xy-12y4-z2
==> 
==> 
derivation psi = derivationFromPoly(0); psi;
==>  Omega_R^1 --> R
==>        dx |--> 0
==>        dy |--> 0
==>        dz |--> 0
==> 
==> 
kill Omega_R,dx,dy,dz,phi,psi;
See also: derivationConstructor; derivationFromList.