frobeniusNorm method
Computes the frobenius norm. It's the squareroot of the sum of all squared matrix elements.
Implementation
double frobeniusNorm() {
final e = elements;
double norm = 0;
for ( int i = 0; i < 9; i ++ ) {
norm += e[ i ] * e[ i ];
}
return math.sqrt( norm );
}