Given an matrix
, the Moore-Penrose generalized matrix
inverse is a unique
matrix pseudoinverse
.
This matrix was independently defined by Moore in 1920 and Penrose (1955), and variously
known as the generalized inverse, pseudoinverse, or Moore-Penrose inverse. It is
a matrix 1-inverse, and is implemented in the
Wolfram Language as PseudoInverse[m].
The Moore-Penrose inverse satisfies
(1)
| |||
(2)
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(3)
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(4)
|
where
is the conjugate transpose.
It is also true that
(5)
|
is the shortest length least squares solution to the problem
(6)
|
If the inverse of exists, then
(7)
|
as can be seen by premultiplying both sides of (6) by to create a square matrix
which can then be inverted,
(8)
|
giving
(9)
| |||
(10)
|