** Matrix or vector norm. **

** For matrices.. **

** NORM(X) is the largest singular value of X, max(svd(X)). **

** NORM(X,2) is the same as NORM(X). **

** NORM(X,1) is the 1-norm of X, the largest column sum, **

** = max(sum(abs((X)))). **

** NORM(X,inf) is the infinity norm of X, the largest row sum, **

** = max(sum(abs((X')))). **

** NORM(X,'inf') is same as NORM(X,inf). **

** NORM(X,'fro') is the F-norm, sqrt(sum(diag(X'*X))). **

** NORM(X,P) is available for matrix X only if P is 1, 2, inf or 'fro'. **

** **

** **

** For vectors.. **

** NORM(V,P) = sum(abs(V)^P)^(1/P). **

** NORM(V) = norm(V,2). **

** NORM(V,inf) = max(abs(V)). **

** NORM(V,-inf) = min(abs(V)). **

** **

** **

** In MATLAB 4.0, if X has complex components, z, then **

** abs(z) = sqrt(z*conj(z)), not abs(real(z)) + abs(imag(z)), **

** which was used in some earlier versions of MATLAB. **

** **

** **

** See also COND , RCOND , CONDEST , NORMEST . **

** **