Introduction Matrix Action Perpframes, Aligners and Hangers Stretchers Coordinates Projections SVD Matrix Subspaces Linear Systems PseudoInverse Condition Number Matrix Norm Rank One Image Compression Noise Filtering
Todd Will

Matrix
Hits
2D Action 
Matrix Action 
3D
Action
Exercises 

Matrix HitsWhen you hit a point with a matrix you get another point.When the matrix
hits
you get .
Two different ways to compute a matrix times a point.COLUMN WAY to compute : Take a linear combination of the COLUMNS of A using the weights from . E.g.ROW WAY to compute :
Dot each ROW of A with .
2D Matrix ActionThe plot below shows some color coded points on the unit circle. Move your mouse over the plot to see what happens when the matrix hits the points on the unit circle.
Check out a few more.Put your cursor over a matrix to see the matrix hit the unit circle.
You can hit other curves too.Check out the same three matrices hitting a damped sine wave.
3D Matrix ActionIf you have a 3 by 3 matrix you can hit 3D surfaces.Check out the matrix
hitting this surface.
Exercises
