Take the 2-minute tour ×   1. Is there any simple algorithm for
matrix inversion (that can be implemented using C/C++)?    2.
Can QR decomposition be used for matrix inversion? How?
share|improve this question Please clarify what is B"H in the
beginning of the question? –  user21436 Feb 14 '12 at 17:39 It
means with g-d's help (without it there shall be no benefit to
this question, nor to any of the answers to it). –  Yan Raf Feb
14 '12 at 18:14 The first question might be more suitable for
scicomp.SE. –  user2468 Feb 20 '12 at 21:09 add comment  2
Answers  Gauss–Jordan elimination can be used for matrix
inversion.  A QR-decomposition can certainly be used for matrix
inversion because if $A=QR$ then $A^{-1} = R^{-1} Q^{-1} =
R^{-1} Q^{T}$ and $R^{-1}$ is easy to compute because $R$ is
triangular.  But consider why you need to invert a matrix. In
most cases, you don't: you just need to solve a linear system
$Ax=b$. If $A=QR$ then this system is equivalent to $Rx = Q^T
b$, which is easy to solve because $R$ is