previous up next
Go up to Parallel Resultant Computation
Go forward to Sequential Algorithm
RISC-Linz logo

Problem Statement

Let A=SUMi=0mAi xi and B=SUMi=0nBi xi be non-zero polynomials over an integral domain I, i.e.,

A, B inI[x]
The Sylvester matrix of A and B is the m+n by m+n matrix
Am Am-1 ... A0
... ... ... ...
Am Am-1 ... A0
Bn Bn-1 ... B0
... ... ... ...
Bn Bn-1 ... B0
whose upper part consists of n rows of the coefficients of A and whose lower part consists of m rows of the coefficients of B (all entries not shown are zero). The resultant of A and B is the determinant of this matrix, i.e.,
Resultant(A,B) inI.

In the context of the plotting of algebraic curves, we are interested in the special case where A and B are polynomials in r variables over the integers, i.e., given

A,B inZ[x1,...,xr-1][xr]
we want to find
Resultant(A,B) inZ[x1,...,xr-1].
For plotting algebraic curves in two dimensions, we have to solve this problem for r=2.
Maintained by: Wolfgang Schreiner
Last Modification: April 22, 1999

previous up next