What is a matrix norm?

What is a matrix norm?

A matrix norm is a norm on ). Thus, the matrix norm is a function The only feature distinguishing matrices from rearranged vectors is multiplication. Matrix norms are particularly useful if they are also sub-multiplicative:

How do you find the maximum norm of a vector?

, and use one of the familiar vector norms. For example, using the p -norm for vectors, p ≥ 1, we get: This is a different norm from the induced p -norm (see above) and the Schatten p -norm (see below), but the notation is the same. The special case p = 2 is the Frobenius norm, and p = ∞ yields the maximum norm.

What is a norm in math?

For the general concept, see Norm (mathematics). In mathematics, a matrix norm is a vector norm in a vector space whose elements (vectors) are matrices (of given dimensions).

How do you find the norm of an entrywise matrix?

“Entrywise” matrix norms. For example, using the p -norm for vectors, p ≥ 1, we get: This is a different norm from the induced p -norm (see above) and the Schatten p -norm (see below), but the notation is the same. The special case p = 2 is the Frobenius norm, and p = ∞ yields the maximum norm.

What is the spectral norm of a matrix?

The spectral norm of a matrix is the largest singular value of (i.e., the square root of the largest eigenvalue of the matrix

What is the Frobenius norm of a matrix?

is the Frobenius norm. Equality holds if and only if the matrix is a rank-one matrix or a zero matrix. This inequality can be derived from the fact that the trace of a matrix is equal to the sum of its eigenvalues. .

How do you know if a matrix norm is increasing?

Thus, a matrix norm is increasing if A ≼ B ⇒ ‖ A ‖ ≤ ‖ B ‖ . {\\displaystyle A\\preccurlyeq B\\Rightarrow \\|A\\|\\leq \\|B\\|.} The Frobenius norm and spectral norm are examples of monotone norms. Another source of inspiration for matrix norms arises from considering a matrix as the adjacency matrix of a weighted, directed graph.