Redheffer[P]

Aliases: None

Description: $Redheffer[P]$ gives the inverse of chain.
Redheffer $[Chain[P]] = P = Chain[$Redheffer$[P]]$.

Arguments: $P$ is a block $2\times 2$ matrix.

Comments / Limitations: $Redheffer[P]$ assumes the invertiblity of the entries of $P$.