Visual Fitting is an editor to be able to represent mathematical data which, from a list of values you indicate, can draw lines, non-linear curves, or non-liner surface models.
From Visual Fitting you can represent any binary function model. It has a practical data editor (very similar to an Excel worksheet) to insert the values.
Each of the resulting graphs can be moved and rotated. You can also zoom in and out of set areas of the graph. That graph can be saved in BMP format.