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Cremona :: isInverseMap(RationalMap,RationalMap)

isInverseMap(RationalMap,RationalMap) -- checks whether two rational maps are one the inverse of the other

Synopsis

Function: isInverseMap
Usage:

isInverseMap(phi,psi)
Inputs:
- phi, a rational map
- psi, a rational map
Outputs:
- a Boolean value, whether phi * psi == 1 and psi * phi == 1
Consequences:
- If the answer is affirmative, then the system will be informed and so commands like 'inverse phi' will execute fast.

See also

RationalMap == RationalMap -- equality of rational maps
RationalMap * RationalMap -- composition of rational maps
isInverseMap(RingMap,RingMap) -- checks whether a rational map is the inverse of another
inverse(RationalMap) -- inverse of a birational map
forceInverseMap -- declare that two rational maps are one the inverse of the other

Ways to use this method:

isInverseMap(RationalMap,RationalMap) -- checks whether two rational maps are one the inverse of the other