Macaulay2 » Documentation
Packages » CorrespondenceScrolls :: irrelevantIdeal
next | previous | forward | backward | up | index | toc

irrelevantIdeal -- returns the irrelevant ideal of a multi-graded ring

Description

Returns the intersection of the ideals of variables in each single multi-degree.

i1 : R = productOfProjectiveSpaces 3

o1 = R

o1 : PolynomialRing
 
i2 : vars R

o2 = | x_(0,0) x_(0,1) x_(1,0) x_(1,1) x_(2,0) x_(2,1) |

             1      6
o2 : Matrix R  <-- R
 
i3 : (gens R)/degree

o3 = {{1, 0, 0}, {1, 0, 0}, {0, 1, 0}, {0, 1, 0}, {0, 0, 1}, {0, 0, 1}}

o3 : List
 
i4 : irrelevantIdeal R

o4 = ideal (x   x   x   , x   x   x   , x   x   x   , x   x   x   ,
             0,1 1,1 2,1   0,0 1,1 2,1   0,1 1,0 2,1   0,0 1,0 2,1 
     ------------------------------------------------------------------------
     x   x   x   , x   x   x   , x   x   x   , x   x   x   )
      0,1 1,1 2,0   0,0 1,1 2,0   0,1 1,0 2,0   0,0 1,0 2,0

o4 : Ideal of R

See also

For the programmer

The object irrelevantIdeal is a function closure.

The source of this document is in CorrespondenceScrolls.m2:541:0.