@Barmaley.exe for the data in vectors as per Mahalanobis distance formula.

Barmaley.exe can you evaluate the distance between two row vectors I provided above? Thanks!

I've stated software I am using - R and Matlab. The problem has been discussed at least once on this site, with no solution provided. Most software packages are clear that in a matrix or data frame , then number of rows must be greater than the number of columns for procedures able to evaluate the distance. Now, I am thinking of finding unbiased estimator of the distance that does not require inverse of covariance matrix.

If I have them as rows, software packages cannot evaluate the distance, as the number of rows must exceed the number of columns.

Thanks for your reply! I know the formula. I cannot calculate Mahalanobis distance having vectors as rows, that v1 is 1x18 and and v2 is 1x18 using R or Matlab. However, I can calculate using these vectors as columns, but that's not what I am after.