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DA.NthDerivation

Computes the N-th derivation of a differential polynomial.
Syntax
          
DA.NthDerivation(F:POLY, N:INT):POLY

          

Description
Computes the N-th derivation of the differential polynomial F. If the order of the result would exceed the given maximum order as implied by the current ring, an error is thrown.

Example
Use QQ[x[1..2,0..20]];
F:=x[1,2]^2*x[1,1]-x[2,4]^3;
DA.NthDerivation(F, 2);
-------------------------------
5x[1,2]^2x[1,3] + 2x[1,1]x[1,3]^2 + 2x[1,1]x[1,2]x[1,4] - 6x[2,4]x[2,5]^2 - 3x[2,4]^2x[2,6]
-------------------------------


Example
Use Q[x[1..2,0..20]];
F:=x[1,2]^2*x[1,1]-x[2,4]^3;
DA.NthDerivation(F, 20);
-------------------------------
ERROR: Maximum order is exceeded.
CONTEXT: Error("Maximum order is exceeded.")
-------------------------------


See Also