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7.5.5.0. fl2poly
Procedure from library dmodapp.lib (see dmodapp_lib).

Usage:
fl2poly(L,s); L a list, s a string

Return:
poly

Purpose:
reconstruct a monic polynomial in one variable from its factorization

Assume:
s is a string with the name of some variable and
L is supposed to consist of two entries:
- L[1] of the type ideal with the roots of a polynomial
- L[2] of the type intvec with the multiplicities of corr. roots

Example:
 
LIB "dmodapp.lib";
ring r = 0,(x,y,z,s),Dp;
ideal I = -1,-4/3,0,-5/3,-2;
intvec mI = 2,1,2,1,1;
list BS = I,mI;
poly p = fl2poly(BS,"s");
p;
==> s7+7s6+173/9s5+233/9s4+154/9s3+40/9s2
factorize(p,2);
==> [1]:
==>    _[1]=s+2
==>    _[2]=3s+4
==>    _[3]=3s+5
==>    _[4]=s
==>    _[5]=s+1
==> [2]:
==>    1,1,1,2,2


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