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map(Module) -- identity map

Synopsis

Usage:
map M
Function: map
Inputs:
- M, a module
Outputs:
- a matrix, the identity map on M
Optional inputs:
- Degree => ..., -- set the degree of a map
- DegreeLift => ..., -- make a ring map
- DegreeMap => ..., -- make a ring map

Description

i1 : f = map ZZ^3

o1 = | 1 0 0 |
     | 0 1 0 |
     | 0 0 1 |

              3        3
o1 : Matrix ZZ  <--- ZZ

i2 : g = id_(ZZ^3)

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

              3        3
o2 : Matrix ZZ  <--- ZZ

i3 : f === g

o3 = true

Caveat

may be removed

See also

id _ Module -- identity map