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TestIdeals :: ascendIdeal(..., AscentCount => ...)

ascendIdeal(..., AscentCount => ...) -- return how many times it took before the ascent of the ideal stabilized

Synopsis

Description

By default (when AscentCount => true), ascendIdeal just returns the stable (ascended) ideal. If instead you set AscentCount=>true then it returns a list. The first value is the stable ideal. The second is how many steps it took to reach that ideal.

i1 : R = ZZ/5[x,y,z];
i2 : J = ideal(x^12,y^15,z^21);

o2 : Ideal of R
i3 : f = y^2+x^3-z^5;
i4 : ascendIdeal(1, f^4, J)

o4 = ideal (z, y, x)

o4 : Ideal of R
i5 : ascendIdeal(1, f^4, J, AscentCount=>true)

o5 = {ideal (z, y, x), 3}

o5 : List

Further information