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# idealChainFromShelling -- Produces chains of ideals from a shelling.

- Usage:
    `L = idealChainFromShelling(P)`
    `L = idealChainFromShelling(R,P)`
- Inputs:
  - R, a ring, Polynomial ring
  - P, a list, A (possibly impure) shelled simplicial complex, represented by a list of lists of integers. Each list of integers is a facet of the complex and the order is a shelling. If the ring R is specified, the output is a list of ideals in R; else it is a list of ideals in QQ[x_0..x_{n-1}], where n is the maximum number of elements in one of the lists of integers
- Outputs:
  - L, a list, a list of ideals

## Description

Outputs the Stanley-Reisner ideal for each successive simplicial complex formed by truncating the shelling.

    i1 : P =  {{1, 2, 4}, {0, 1, 4}, {0, 2, 4}, {0, 3, 4}};

    i2 : idealChainFromShelling(P)

    o2 = {monomialIdeal (x , x ), monomialIdeal (x x , x ), monomialIdeal
                          0   3                   0 2   3
         ------------------------------------------------------------------------
         (x x x , x ), monomialIdeal (x x x , x x , x x )}
           0 1 2   3                   0 1 2   1 3   2 3

    o2 : List

## See also

- idealFromShelling -- Produces an ideal from a shelling
- randomShellableIdealChain -- Produces a chain of ideals from a random shelling

## Ways to use idealChainFromShelling:

- `idealChainFromShelling(List)`
- `idealChainFromShelling(Ring,List)`

## For the programmer

The object idealChainFromShelling is a method function.

The source of this document is in /build/macaulay2-88fgJW/macaulay2-1.25.11+ds/M2/Macaulay2/packages/RandomIdeals.m2:679:0.