The first example compares the results of subs and dsubs.
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In this case subs returns an expression which contains f', the object being substituted.
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Here, dsubs completely removes the f', the left hand side of the substitution equation.
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Here is a PDE example.
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The dsubs command also works with anticommutative variables, natively, without using the approach explained in PerformOnAnticommutativeSystem.
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Set first and as suffixes for variables of type/anticommutative (see Setup)
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A PDE system example with two unknown anticommutative functions of four variables, two commutative and two anticommutative; to avoid redundant typing in the input that follows and redundant display of information on the screen let's use PDEtools:-diff_table PDEtools:-declare
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Now we can enter derivatives directly as the function's name indexed by the differentiation variables and see the display the same way; two PDEs
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By inspection, it is clear that the derivatives in pde[2] can be substituted in pde[1] reducing the problem to a simpler one:
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Substituting this result for back into pde[2], then multiplying by and subtracting from the above also leads to the PDE system solution, that in this case can also be obtained using a different technique passing the whole system directly to pdsolve