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D.5.2.5 chern

Procedure from library chern.lib (see chern_lib).

Usage:
chern(s); s list of polynomials

Return:
list of polynomials

Purpose:
computes the list of the Chern classes up to degree N in terms of the Segre classes from s

Note:

Example:
 
LIB "chern.lib";
ring r = 0, (s(1..3)), dp;
list l=s(1..3);
// Chern classes in Segre classes s(1), s(2), s(3)
print( chern(l) );
==> [1]:
==>    -s(1)
==> [2]:
==>    s(1)^2-s(2)
==> [3]:
==>    -s(1)^3+2*s(1)*s(2)-s(3)
// This procedure is inverse to segre(...). Indeed:
print( segre(chern(l), 3) );
==> [1]:
==>    s(1)
==> [2]:
==>    s(2)
==> [3]:
==>    s(3)