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Macaulay2Doc :: rank

rank -- compute the rank

Synopsis

Usage:

rank M
Inputs:
- M, a module, a coherent sheaf, a graded module, a chain complex, or a matrix
Outputs:
- the rank of M

Description

i1 : R = ZZ/101[x,y,z]

o1 = R

o1 : PolynomialRing

i2 : p = vars R;

             1       3
o2 : Matrix R  <--- R

i3 : rank kernel p

o3 = 2

i4 : rank cokernel p

o4 = 0

i5 : C = res cokernel p

      1      3      3      1
o5 = R  <-- R  <-- R  <-- R  <-- 0
                                  
     0      1      2      3      4

o5 : ChainComplex

i6 : rank C

o6 = 0

Ways to use `rank` :

"rank(CoherentSheaf)"
"rank(GradedModule)"
"rank(Matrix)"
"rank(Module)"
"rank(MutableMatrix)"

For the programmer

The object rank is a method function.