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liesymm

 wcollect
 regroup the terms as a sum of products

 Calling Sequence wcollect(expr)

Parameters

 expr - expression involving wedge products

Description

 • This routine is part of the liesymm package and is loaded via with(liesymm).
 • The expression is rewritten in a sum of products form with each distinct wedge product or 1-form occurring exactly once. As the arguments to a wedge product are sorted into address'' order and coefficients are automatically extracted,  $\left(d\left(x\right)\right)&^\left(d\left(t\right)\right)$ is recognized as being the same as $-\left(d\left(t\right)\right)&^\left(d\left(x\right)\right)$.

Examples

 > $\mathrm{with}\left(\mathrm{liesymm}\right):$$\mathrm{setup}\left(x,y,z\right):$
 > $\mathrm{wcollect}\left(a\left(d\left(x\right)\right)&^\left(d\left(y\right)\right)+b\left(d\left(x\right)\right)&^\left(d\left(y\right)\right)\right)$
 $\left({a}{+}{b}\right){}\left({d}{}\left({x}\right)\right){&^}\left({d}{}\left({y}\right)\right)$ (1)
 > $\mathrm{wcollect}\left(a\left(d\left(x\right)\right)&^\left(d\left(y\right)\right)+b\left(d\left(y\right)\right)&^\left(d\left(x\right)\right)\right)$
 $\left({a}{-}{b}\right){}\left({d}{}\left({x}\right)\right){&^}\left({d}{}\left({y}\right)\right)$ (2)