Polar Decomposition Calculator

Decompose any square matrix A into A = UP, where U is orthogonal/unitary and P is positive semidefinite

Matrix Input

Currently supports 2×2 real matrices

[
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Enter real numbers. Complex numbers (with i notation) have limited support.

Polar Decomposition Results

Original Matrix A:

[1.00002.0000]
[3.00004.0000]

Orthogonal Matrix U:

[-0.51450.8575]
[0.85750.5145]

Positive Semidefinite Matrix P:

[2.05802.4010]
[2.40103.7730]

Verification (A = U × P):

[1.00002.0000]
[3.00004.0000]

✓ Polar decomposition successful! The matrix A has been decomposed into A = UP where U is orthogonal and P is positive semidefinite.

Example: Simple 2×2 Matrix

Try this example:

Matrix A = [[1, 2], [3, 4]]

This will decompose into orthogonal matrix U and positive semidefinite matrix P.

Properties

U

Orthogonal Matrix

U^T × U = I (identity matrix)

Preserves lengths and angles

P

Positive Semidefinite

P = P^T and all eigenvalues ≥ 0

Represents scaling and shearing

Always Exists

Every matrix has a polar decomposition

Uniqueness depends on invertibility

Tips

For invertible matrices, polar decomposition is unique

P = √(A^T A) is the positive square root

Similar to polar form of complex numbers

Used in mechanics, computer graphics, and statistics

Understanding Polar Decomposition

What is Polar Decomposition?

Polar decomposition is a matrix factorization that expresses any square matrix A as the product of an orthogonal (or unitary) matrix U and a positive semidefinite matrix P: A = UP.

Mathematical Properties

  • Existence: Every square matrix has a polar decomposition
  • Uniqueness: Unique if A is invertible
  • Orthogonal U: U^T U = I for real matrices
  • Positive P: P = P^T with non-negative eigenvalues

Calculation Method

1. Compute A^T A (or A* A for complex)

2. Find P = √(A^T A)

3. If A is invertible: U = A P^(-1)

4. Otherwise: Use SVD method

Applications

  • Computer Graphics: Decompose transformations
  • Mechanics: Separate rotation and deformation
  • Statistics: Principal component analysis
  • Signal Processing: Matrix factorization