ApCoCoA-1:DA.NthDerivation
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Revision as of 12:05, 8 December 2008 by S schuster (talk | contribs) (New page: <command> <title>diffalg.NthDerivation</title> <short_description>Computes the n-th derivation of a differential polynomial.</short_description> <syntax> $diffalg.NthDerivation(F:P...)
diffalg.NthDerivation
Computes the n-th derivation of a differential polynomial.
Syntax
$diffalg.NthDerivation(F:POLY, N:INT):POLY
Description
Computes the N-th derivation of the differential polynomial F. If the order exceeds the allowed maximum order, the function throws an error.
Example
Use Q[x[1..2,0..20]];
F:=x[1,2]^2*x[1,1]-x[2,4]^3;
$diffalg.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]
-------------------------------
Use Q[x[1..2,0..20]];
F:=x[1,2]^2*x[1,1]-x[2,4]^3;
$diffalg.NthDerivation(F, 20);
-------------------------------
ERROR: Maximum order is exceeded.
CONTEXT: Error("Maximum order is exceeded.")
-------------------------------
