Conversions between diff, D, and Physics[diff] - convert derivatives between the diff and D notations
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Calling Sequence
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convert(expr, diff)
convert(expr, D)
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Parameters
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expr
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any valid Maple object
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Description
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convert/D and convert/diff are converter routines between the D and diff formats for representing derivatives. The equivalence for anticommutative high order derivatives written in the D format and diff format of the Physics package is as in:
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Physics[diff](f(theta1,theta2),theta1,theta2) = D[1,2](f)(theta1,theta2);
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Examples
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Load the Physics package and set a prefix to identify anticommutative variables (see Setup for more information).
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Consider a commutative function depending on commutative and anticommutative variables, and one higher order derivative of it.
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Note in the above that the commutative differentiation variables are collected as a group to be applied first, then the anticommutative ones.
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Physics:-diff(Physics:-diff(Physics:-diff(diff(diff(diff(f(x, y, z, theta1, theta2, theta3), x), y), z), theta1), theta2), theta3)
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Rewrite this expression in D notation, then convert back to diff notation.
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