vecnorm

vecnorm(A, [p])

For any iterable container A (including arrays of any dimension) of numbers (or any element type for which norm is defined), compute the p-norm (defaulting to p=2) as if A were a vector of the corresponding length.

For example, if A is a matrix and p=2, then this is equivalent to the Frobenius norm.

Examples

Compute the Euclidean norm of a vector:
```
julia> vecnorm([3, 4])
5.0
```
This example calculates the Euclidean norm (p=2 norm) of the vector [3, 4].
Calculate the 1-norm of a matrix:
```
julia> mat = [1 2; -3 4];
julia> vecnorm(mat, 1)
5.0
```
It computes the 1-norm (sum of absolute values) of the matrix mat treating it as a vector.
Calculate the infinity norm of a matrix:
```
julia> mat = [1 2; -3 4];
julia> vecnorm(mat, Inf)
7.0
```
This example computes the infinity norm (maximum absolute row sum) of the matrix mat as if it were a vector.
Compute the Frobenius norm of a matrix:
```
julia> mat = [1 2; -3 4];
julia> vecnorm(mat)
5.477225575051661
```
It calculates the Frobenius norm (p=2 norm) of the matrix mat.

Common mistake example:

julia> vecnorm([1, 2, 3], -1)
ERROR: ArgumentError: Invalid value for p-norm: -1

In this example, -1 is provided as the p value, which is not a valid input. The p value should be a positive number or Inf.

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vecnorm

Examples

See Also

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