This page is about vectors, scalars and matrices in 2D
Cartesian axes are shown, x to the right and y up the screen, both with ranges + and - 10.
u and v are vectors. The 'show' buttons toggle the display or hiding of these.
The x and y components of u are also shown in red.
The check-boxes select one of u and v, and the vector can then be changed with the keyboard. q w increases and decreases the x component, and a s the y component.
a is a scalar, initially 2. The + and -buttons alter this by 0.1
Vectors au and u+v can be displayed. au may be in the same place as u and hide it.
M is a 2X2 matrix, with components from the keyboard
Vector Mu can be shown, as a matrix transform.