Update Inverse Matrix

update inverse of matrix after appending or reducing one coulmn and one row.

Inverse calculation is expensive. However, if updating the inverse of a matrix appending or reducing one coulm and one row can be performed much fast. This package includes two small tools, invupdateapp and invupdatered, to update inverse much faster than directly calculation of the inverse. It is based on the block matrix formular. Other rank 1 update functions in MATLAB are qrupdate and cholupdate.

Both functions have been updated to improve performance and functionality.