next | previous | forward | backward | up | top | index | toc | Macaulay2 web site
NumericalHilbert :: truncate(DualSpace,ZZ)

truncate(DualSpace,ZZ) -- truncate a polynomial space or dual space

Synopsis

Description

Truncates a dual space or polynomial space T so that the total degree of all terms does not exceed d.

i1 : R = CC[x,y];
i2 : I = ideal {x-y};

o2 : Ideal of R
i3 : D = truncatedDual(origin R, I, 5)

o3 = | 1 .707107x+.707107y .5x2+.5xy+.5y2 .353553x3+.353553x2y+.353553xy2+.353553y3 .25x4+.25x3y+.25x2y2+.25xy3+.25y4 .176777x5+.176777x4y+.176777x3y2+.176777x2y3+.176777xy4+.176777y5 |

o3 : DualSpace
i4 : truncate(D, 3)

o4 = | x3+1x2y+1xy2+1y3 x2+1xy+1y2 x+y 1 |

o4 : DualSpace