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TriangularSets :: initial

initial -- initial of a polynomial

Synopsis

Description

Returns the initial of a polynomial. The initial of a polynomial f is the the leading coefficient of f viewed as a univariate polynomial in its main variable.

i1 : R = QQ[x_0..x_3, MonomialOrder=>Lex];
i2 : f = x_1^2*(x_2*x_3+2*x_3) + x_1*(x_2^2-1) + (x_2-x_3)

      2         2        2
o2 = x x x  + 2x x  + x x  - x  + x  - x
      1 2 3     1 3    1 2    1    2    3

o2 : R
i3 : initial f

o3 = x x  + 2x
      2 3     3

o3 : R

See also

Ways to use initial :