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D.12.7.13 symmfunc
Procedure from library rootsmr.lib (see rootsmr_lib).
- Usage:
- symmfunc(s); s list
- Return:
- list: the symmetric functions of the roots of a polynomial, given
the power sums of those roots.
Example:
| LIB "rootsmr.lib";
ring r = 0,x,dp;
poly p = (x-1)*(x-2)*(x-3);
list psums = list(1+2+3,1+4+9,1+8+27);
list l = symmfunc(psums);
l;
==> [1]:
==> 1
==> [2]:
==> -6
==> [3]:
==> 11
==> [4]:
==> -6
p; // Compare p with the elements of l
==> x3-6x2+11x-6
| See also:
powersums.
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