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# padASM -- pad an ASM with an identity matrix

- Usage:
    `padASM(A, n)`
- Inputs:
  - A, a matrix,
  - n, an integer,
- Outputs:
  - a matrix,

## Description

Given an alternating sign matrix, pads the ASM pads an ASM with a block of an $n\times n$ identity matrix to the bottom right of the original ASM.

    i1 : A = matrix{{0, 0, 1, 0}, {1, 0, 0, 0}, {0, 1, -1, 1}, {0, 0, 1, 0}};

                  4       4
    o1 : Matrix ZZ  <-- ZZ

    i2 : padASM(A,3)

    o2 = | 0 0 1  0 0 0 0 |
         | 1 0 0  0 0 0 0 |
         | 0 1 -1 1 0 0 0 |
         | 0 0 1  0 0 0 0 |
         | 0 0 0  0 1 0 0 |
         | 0 0 0  0 0 1 0 |
         | 0 0 0  0 0 0 1 |

                  7       7
    o2 : Matrix ZZ  <-- ZZ

## Ways to use padASM:

- `padASM(Matrix,ZZ)`

## For the programmer

The object padASM is a method function.

The source of this document is in /build/macaulay2-88fgJW/macaulay2-1.25.11+ds/M2/Macaulay2/packages/MatrixSchubert/MatrixSchubertConstructionsDOC.m2:558:0.