# Matrix norm Calculator

## Calculates the L1 norm, the Euclidean (L2) norm and the Maximum(L infinity) norm of a matrix. | ||||

Matrix norm

[1-5] /5 | Disp-Num |

- Purpose of use
- To double-check my L2 norm calculations.
- Bug report
- Incoorect L2 norm computed for the following matrix:

2 -1 0 0

-1 2 -1 0

0 -1 2 -1

0 0 -1 2

Maximum eigenvalue for this symmetric matrix is 3.61803398875

Not 2.61803398875, as calculated here. - from Keisan
- Thank you for your advice.

We've fixed the bug.

[1] 2019/12/09 13:44 Male / 20 years old level / High-school/ University/ Grad student / Useful /

- Purpose of use
- Learn L2 norm

[2] 2019/10/15 11:31 Male / 20 years old level / High-school/ University/ Grad student / Very /

- Purpose of use
- homework check

[3] 2019/10/02 07:09 Male / Under 20 years old / High-school/ University/ Grad student / Very /

- Purpose of use
- learning how to norm matrix for my work.

The examples helps

[4] 2019/08/18 15:44 Female / 40 years old level / An office worker / A public employee / A little /

- Bug report
- The text definition of the L2 norm is incorrect. The calculated result is correct though.

Is says it''s the maximum eigenvalue of A, that is lambda_max(A).

Instead it should say that it''s the largest spectral radius, that is sigma_max(A).

Equivalently that''s the largest eigenvalue of A^T.A (or A^* A for complex matrices).

See e.g. https://en.wikipedia.org/wiki/Matrix_norm - from Keisan
- Thank you for your advice.

We have fixed it.

[5] 2018/01/20 05:51 Male / 50 years old level / An engineer / Useful /

**To improve this 'Matrix norm Calculator', please fill in questionnaire.**

**The hyperlink to [Matrix norm]**