Dear list

i have some 15 X 15 matrices - which are Hessian , and they are suppose to be Symmetric, generated from some quantum mechanical packages.

the problem is - All these matrices are NON SYMMETRIC.
Since i need to Quantify the OVERALL - ERROR of these matrices with respect to THE IDEAL Hessian that i already have, HOW CAN I DO THAT ?

OF COURSE I can compare EACH AND EVERY element of the matrices and that of ideal Hessian and take a difference, or just compare the DIAGONAL ELEMENT DIFFERENCE / DETERMINENTS of these matrices and ideal.

BUT I REALLY NEED A SINGLE-VALUED QUANTITY TO MEASURE IT.

I CHECKED THE N.R. IN C, but i did not find any info abt this-explicitly.

DOES ANYBODY HELP ME TO SOLVE THIS PROBLEM.

[I THINK SOMEBODY HAVE A SUFFICIENT STATISTICAL DATA ANALYSIS CAN GIVE A SHORT ANSWER EASILY ...!]

THANKS & CHEERS

KRISHNA