ApCoCoA-1:DA.InitialOfDer

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DA.InitialOfDer

Computes the initial wrt. a given derivative.

Syntax

DA.InitialOfDer(F:POLY, X:INDET):POLY

Description

DA.InitialOfDer returns the polynomial leading coefficient of polynomial F regarded as polynomial in the derivative X.

  • @param F A differential polynomial.

  • @param X A indeterminate.

  • @return Initial of F wrt. X.

Example

Use Q[x[1..2,0..20]];
Use Q[x[1..2,0..20]], Ord(DA.DiffTO("Lex"));

F:=x[1,2]^3x[2,2]^2 + x[1,1]^3x[2,2]^2 + 1/4x[1,2];

DA.InitialOfDer(F, x[1,2]);
-------------------------------
x[2,2]^2
-------------------------------

DA.Initial

DA.DiffTO