Algorithm for “nice” grid line intervals on a graph

Question

I need a reasonably smart algorithm to come up with \"nice\" grid lines for a graph (chart).

For example, assume a bar chart with values of 10, 30, 72 and 60. You k

Answer 1

In python:

steps = [numpy.round(x) for x in np.linspace(min, max, num=num_of_steps)]