SVD
Decomposes any matrix as \(A=U\Sigma V^{\mathsf T}\). For a 2D transform, \(V\) gives input directions, singular values give stretch, and \(U\) gives output directions.
Explore SVD, PCA, and EVD through one focused input, one visualization, and the key numbers.
2 · See what happens
SVD maps the unit circle to an ellipse. Principal directions become ellipse axes.
Column 1 of A is the purple arrow A e₁. Column 2 is the cyan arrow A e₂.
3 · Read the result
Run analysis to see the decomposition.
SVD separates rotation from axis scaling. Compare the singular values to see whether one direction is stretched more strongly.
\(A=U\Sigma V^{\mathsf T}\)
Decomposes any matrix as \(A=U\Sigma V^{\mathsf T}\). For a 2D transform, \(V\) gives input directions, singular values give stretch, and \(U\) gives output directions.
Runs eigendecomposition on a covariance matrix. The largest eigenvalue points to the direction with the most variance.
Decomposes a square matrix as \(A=V\Lambda V^{-1}\) when enough independent eigenvectors exist. It exposes invariant directions of the transform.