# Making maps between chain complexes -- information about the basic constructors

## Canonical maps between complexes

Some complexes come with canonical maps. To access the complex map, one uses canonicalMap(Complex,Complex). The following operations have associated canonical maps.

## Random maps of chain complexes

The method randomComplexMap(Complex,Complex) allows one to construct random complex maps, random morphisms between complexes, and random null homotopies between complexes.