Introduction - If you have any usage issues, please Google them yourself
This function calculates the POD basis vectors
Function inputs:
X : (n x nsnap) snapshot matrix
n = number of states in full space
nsnap = number of snapshots
cenergy : how much energy of the ensemble you want
to capture, i.e. cenergy = 99.9 (percent)
Function outputs:
phi : (n x nsnap) matrix containing POD basis vectors
lam : (nsnap x 1) vector containing POD eigenvalues
Xmean : (n x 1) the mean of the ensemble X
nbasis : number of POD basis vectors you should use
to capture cenergy (percent) of the ensemble