Matrix Norm Calculator

Calculate 1-norm, ∞-norm, 2-norm, Frobenius norm, and max norm with step-by-step solutions

Matrix Norm Calculator

Matrix Dimensions

Norm Types

1-norm: Max column sum
∞-norm: Max row sum
2-norm: Spectral norm
Frobenius: Matrix Euclidean
Max norm: Largest element

Matrix Norms

Matrix A (2×2)

[22]
[13]

1-Norm

5
Maximum column sum

∞-Norm

4
Maximum row sum

2-Norm

4.1306
Spectral norm

Frobenius Norm

4.2426
Matrix Euclidean norm

Max Norm

3
Maximum element

A^T·A Trace

18.0000
For Frobenius calculation

A^T·A (for norm calculations)

[57]
[713]

Step-by-Step Calculations

1-NORM CALCULATION (Maximum absolute column sum):
Column 1: 2 + 1 = 3
Column 2: 2 + 3 = 5
||A||₁ = max(3, 5) = 5
INFINITY NORM CALCULATION (Maximum absolute row sum):
Row 1: 2 + 2 = 4
Row 2: 1 + 3 = 4
||A||∞ = max(4, 4) = 4
MAX NORM CALCULATION (Maximum absolute value):
||A||max = max(2, 2, 1, 3) = 3
FROBENIUS NORM CALCULATION:
A^T·A trace = 18
||A||F = √(18) = 4.2426
2-NORM CALCULATION (Spectral norm):
Largest eigenvalue of A^T·A = 17.0623
||A||₂ = √(17.0623) = 4.1306

Example Calculations

2×2 Matrix Example

Matrix A:

[2 2]
[1 3]

Norms:

• ||A||₁ = max(3, 5) = 5
• ||A||∞ = max(4, 4) = 4
• ||A||max = 3
• ||A||F ≈ 4.690

3×3 Matrix Example

Matrix A:

[2 2 6]
[1 3 9]
[6 1 0]

Norms:

• ||A||₁ = max(9, 6, 15) = 15
• ||A||∞ = max(10, 13, 7) = 13
• ||A||max = 9
• ||A||F ≈ 13.115

Matrix Norm Types

1-Norm

||A||₁ = max column sum

Maximum absolute sum of matrix columns

∞-Norm

||A||∞ = max row sum

Maximum absolute sum of matrix rows

2-Norm

||A||₂ = √λ_max(A^T·A)

Spectral norm, induced by vector 2-norm

Frobenius

||A||F = √trace(A^T·A)

Matrix Euclidean norm

Max Norm

||A||max = max|a_ij|

Largest absolute value in matrix

Norm Properties

Non-negativity: ||A|| ≥ 0

Zero norm: ||A|| = 0 ⟺ A = 0

Homogeneity: ||cA|| = |c|·||A||

Triangle inequality: ||A+B|| ≤ ||A|| + ||B||

Submultiplicative: ||AB|| ≤ ||A||·||B||

Equivalence: All norms are equivalent

Understanding Matrix Norms

What is a Matrix Norm?

A matrix norm is a function that assigns a non-negative real number to every matrix, representing the "size" or "magnitude" of the matrix. Unlike vector norms, matrix norms often represent the maximum stretching factor when the matrix acts on unit vectors.

Mathematical Definition

Induced Matrix Norm:

||A|| = max(||Ax||) where ||x|| = 1

Applications

  • Condition number calculations
  • Numerical stability analysis
  • Convergence analysis in iterative methods
  • Machine learning regularization
  • Signal processing and data analysis

Step 1: Choose Norm Type

Select the appropriate norm based on your application: 1-norm, ∞-norm, 2-norm, Frobenius, or max norm.

Step 2: Apply Formula

Use the specific calculation method for your chosen norm type, whether it's sums, eigenvalues, or traces.

Step 3: Interpret Result

Understand what the norm value represents in terms of matrix properties and stretching factors.

Formula Reference

1-norm: ||A||₁ = max_j Σᵢ |aᵢⱼ|
∞-norm: ||A||∞ = max_i Σⱼ |aᵢⱼ|
2-norm: ||A||₂ = √λ_max(A^T A)
Frobenius: ||A||F = √trace(A^T A)
Max norm: ||A||max = max_ij |aᵢⱼ|
General: ||A|| = max(||Ax||/||x||) for x ≠ 0