This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
Piecewise linear functionD.svg Illustration of en piecewise linear function selfmade with en MATLAB June UTC Oleg Alexandrov Source code MATLAB Draw piewiselinear function in two dimensions on given triangulation Due to bug in plotsvg it can't export pictures well Then have to take the picture and rotate and project it manually