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codim(Module) -- codimension of the support of a module

Synopsis

Usage:
codim M
Function: codim
Inputs:
- M, a module, a module over a ring R
Outputs:
- an integer

Description

Computes the codimension of the support of the module as given by dim(R) - dim(M).

i1 : R = ZZ/101[a..d];

i2 : M = coker matrix{{a,b},{c,d}}

o2 = cokernel | a b |
              | c d |

                            2
o2 : R-module, quotient of R

i3 : codim M

o3 = 1

Caveat

The returned value is the usual codimension if R is an integral domain or, more generally, equidimensional.

See also

dim(Module) -- compute the Krull dimension