What does the 'datalim' attribute do?

Question

For a given python plot, what would the following do?

pl.gca().set_aspect('equal', 'datalim')

equal: make 1 increment in the y axis be the same as 1 increment in the x axis. But what does the 'datalim' attribute do?

Answer 1

You specify 'datalim' or 'box'. The former changes the limits on the axes to get the required aspect ration (in your case 1:1). The latter changes the box that being plotted in's aspect ratio.

Feel free to test the two -- the difference should be immediately clear.