[TOC]

`norm`

Norm of a vector or matrix

Usages

`norm(x)`

`norm(x,p)`

x should be a vector, real or complex.
If p is not given, it returns the 2-norm of x, i.e.,

If x is empty, it returns 0.
If p is given, it should be any real positive scalar, -inf or inf.
Depending on the given value of p, it returns the following norms:

`p`	Vector norm
`Inf`	$\max\left\{\|x_1\|,\|x_2\|,\ldots,\|x_n\|\right\}$
`-Inf`	$\min\left\{\|x_1\|,\|x_2\|,\ldots,\|x_n\|\right\}$
Any real positive scalar	$\\|x\\|_p=\left(\|x_1\|^p+\|x_2\|^p+\cdots+\|x_n\|^p\right)^{\frac1{p}}$

`norm(X)`

`norm(X, p)`

X should be a $m\times n$ matrix, real or complex.
If X is empty, it returns 0.
If p is not given, it returns the 2-norm of X, i.e., the largest singular value of X.
If p is given, it should be either 1, 2, or Inf.
Depending on the given value of p, it returns the following norms:

`p`	Matrix norm
1	$\max_{c=1,2,\ldots,n} \sum^m_{r=1}\|x_{rc}\|$
2	The largest singular value of $X$
`Inf`	$\max_{r=1,2,\ldots,m} \sum^n_{c=1}\|x_{rc}\|$