ExcludeMasses
ExcludeMasses
is an option of Apart2
. It allows to specify masses w.r.t which partial fraction decomposition should not be performed, e.g. ExcludeMasses->{m1,m2,3}
.
See also
Overview, Apart2.
Examples
Apart2[FAD[k, {k, m1}, {k, m2}]] // Expand
m12(m12−m22)(k2−m12)1−m12(m12−m22)(k2−m22)1−m12m22(k2−m22)1+k2m12m221
Apart2[FAD[k, {k, m1}, {k, m2}], ExcludeMasses -> m2] // Expand
m12(k2−m12).(k2−m22)1−m12k2.(k2−m22)1