## Function of 2 variables, i.e. f(x,y)

## If f is a scalar quantity, can:

- Make image
- Represent each x,y data point by one or more pixels on screen. Use integer value to represent data value at x,y point (8 bit: 0-255; 24-bit: 0-16.8 million).

- Make contour plot
- Contours are isosurfaces of data.

- Make 3-D surface plot
- Use x,y as 2 coordinates, f as 3rd coordinate, plot surface.

- Make image