FeynAmpDenominatorCombine[expr]
expands expr with
respect to FeynAmpDenominator
and combines products of
FeynAmpDenominator
in expr into one
FeynAmpDenominator
.
Overview, FeynAmpDenominatorSplit.
[q] FAD[q - p]
FAD
= FeynAmpDenominatorCombine[%] ex
\frac{1}{q^2 (q-p)^2}
\frac{1}{q^2.(q-p)^2}
// FCE // StandardForm
ex
(*FAD[q, -p + q]*)
= FeynAmpDenominatorSplit[ex] ex2
\frac{1}{q^2 (q-p)^2}
// FCE // StandardForm
ex2
(*FAD[q] FAD[-p + q]*)