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# describe(FreeOIModuleMap) -- display a free OI-module map

- Function: describe
- Usage:
    `describe phi`
- Inputs:
  - phi, an instance of the type FreeOIModuleMap,
- Outputs:
  - a net,

## Description

Displays the source module, target module, and basis element images of a free OI-module map.

    i1 : P = makePolynomialOIAlgebra(2, x, QQ);

    i2 : F = makeFreeOIModule(e, {1,2}, P);

    i3 : installGeneratorsInWidth(F, 3);

    i4 : b = x_(1,2)*x_(1,1)*e_(3,{2},1)+x_(2,2)*x_(2,1)*e_(3,{1,3},2);

    i5 : C = oiRes({b}, 2);

    i6 : phi = C.dd_1;

    i7 : describe phi

    o7 = Source: (e1, {5, 5}, {-4, -3}) Target: (e0, {3}, {-2})
         Basis element images: {x   x   e0              - x   x   e0
                                 2,3 1,1  5,{2, 4, 5},1    2,4 1,1  5,{2, 3, 5},1
         ------------------------------------------------------------------------
         - x   x   e0              + x   x   e0             , -x   e0
            2,3 1,2  5,{1, 4, 5},1    2,4 1,2  5,{1, 3, 5},1    2,2  5,{1, 3,
         ------------------------------------------------------------------------
              + x   e0              + x   e0              - x   e0             }
         5},1    2,2  5,{1, 3, 4},1    2,3  5,{1, 2, 5},1    2,3  5,{1, 2, 4},1

## Ways to use this method:

- describe(FreeOIModuleMap) -- display a free OI-module map

The source of this document is in /build/macaulay2-88fgJW/macaulay2-1.25.11+ds/M2/Macaulay2/packages/OIGroebnerBases.m2:1979:0.