garyballantyne

A toy problem for compressive sensing

pos:1

Three samples are required to reconstruct a quadratic signal $f(t)=a_0+a_1t+a_2t^2$ (i.e., to find coefficients $a_0$, $a_1$ and $a_2$). Unless, that is, $f$ is sparse (has only one nonzero coefficient) and we apply Compressive Sensing.

Say we know $f$ at two points, (-1,1) and (2,4), as shown by the red squares in