=ADD=
=reftype=
14
=number=
01-01
=url=
ftp://ftp.risc.uni-linz.ac.at/pub/techreports/2001/01-01.ps.gz
=year=
2001
=month=
01
=author=
Sendra; J. Rafael + Winkler; Franz
=title=
Tracing Index of Rational Parametrizations
=abstract=
A rational parametrization of an algebraic curve establishes a rational equivalence
of this curve with the affine or projective line, that is birational if the
parametrization is proper. So, intuitively speaking, a rational parametrization
determines a linear tracing of the curve. Such a parametrization might trace the
curve once or several times. We formally introduce the concept of the tracing
index of a parametrization, we show how to compute it, and we relate it to the
degree of rational reparametrizations as well as to the degree of the curve. 
=sponsor=
First author partially supported by DGES PB98-0713-C02-01 and DGES HU1999-0029.
Second author supported by the Austrian Science Fund (FWF) under Project
SFB F1304, and by \"OAD Acc.Int. Proj.Nr. 19/2000.