# SubResultantPackage(R, UP)¶

intrf.spad line 1 [edit on github]

This package computes the subresultants of two polynomials which is needed for the `Lazard Rioboo’ enhancement to Tragers integrations formula. For efficiency reasons this has been rewritten to call Lionel Ducos package which is currently the best one.

- primitivePart: (UP, R) -> UP if R has EuclideanDomain
`primitivePart(p, q)`

reduces the coefficient of`p`

modulo`q`

, takes the primitive part of the result, and ensures that the leading coefficient of that result is monic.

- subresultantVector: (UP, UP) -> PrimitiveArray UP
`subresultantVector(p, q)`

returns`[p0, ..., pn]`

where`pi`

is the`i`

-th subresultant of`p`

and`q`

. In particular,`p0 = resultant(p, q)`

.