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liesymm

 getcoeff
 extract the coefficient part of a basis wedge product

 Calling Sequence getcoeff(expr)

Parameters

 expr - term involving one wedge product

Description

 • This routine is part of the liesymm package and is loaded via with(liesymm).
 • Given an expression expr involving a single wedge product w find c such that $\mathrm{expr}=cw$.
 • If more than one wedge product is encountered, an error message is given.

Examples

 > $\mathrm{with}\left(\mathrm{liesymm}\right):$$\mathrm{setup}\left(x,y,z\right):$
 > $\mathrm{getcoeff}\left(ad\left(x\right)\right)$
 ${a}$ (1)
 > $\mathrm{getcoeff}\left(ad\left(x\right)+bd\left(x\right)\right)$
 ${a}{+}{b}$ (2)
 > $\mathrm{map}\left(\mathrm{getcoeff},\left[ad\left(x\right),bd\left(y\right)\right]\right)$
 $\left[{a}{,}{b}\right]$ (3)
 > $\mathrm{getcoeff}\left(\frac{1\left(d\left(x\right)\right)&^\left(d\left(y\right)\right)}{c}\right)$
 $\frac{{1}}{{c}}$ (4)
 > $\mathrm{getcoeff}\left(c\right)$
 ${c}$ (5)