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# target(ChainComplexMap) -- find the target of a map of chain complexes

- Function: target
- Usage:
    `target f`
- Inputs:
  - f, a chain complex map
- Outputs:
  - the target chain complex of f

## Description

In the example below, we have a map between two modules and extend it to a map between projective resolutions of the two modules. Then target gives the target of the map of chain complexes.

    i1 : R = ZZ[x,y,z];

    i2 : M = R^1/(x,y,z);

    i3 : N = R^1/(x^2,y^2,x*y*z,z^2);

    i4 : g = map(N,M,x*y);

    o4 : Matrix N <-- M

    i5 : f = res g;

    i6 : target f

          1      4      6      3
    o6 = R  <-- R  <-- R  <-- R  <-- 0

         0      1      2      3      4

    o6 : ChainComplex

(That was an expensive way of resolving N.)

## Ways to use this method:

- target(ChainComplexMap) -- find the target of a map of chain complexes

The source of this document is in /build/macaulay2-88fgJW/macaulay2-1.25.11+ds/M2/Macaulay2/packages/OldChainComplexes/docs/docs.m2:228:0.