Purpose of Inverse...

Hi…

I was wondering what is the purpose of calculating the inverse of a matrix. I know the mathematics behind it and how it’s done, etc. But, in newbie terms, what is the purpose of actually using it?

Thanks,

Bode

It allows you to get back from post-matrix-multiplication vectors/co-ordinates to the original input vector/co-ordinates. In other words, it allows you to do the inverse of the transformation represented in the original matrix.

This only works for invertable matrices of course.

HTH

Jean-Marc

Say you have a matrix A. Since you can multiply A times things, you want to also be able to divide things by A. So for another matrix B, B/A is defined as B*(1/A), and 1/A is defined to be the matrix so that A*(1/A) == 1 (actually not one, but the identity matrix). I.E. 1/A is the inverse of A.

Unfortunately not all matrices have this property, so you can’t do all the fancy arithmetic with matrices that you can with numbers.