Marking axes at irregular intervals

[Razmig K]

Hello everyone,

I have two vectors, x in [-1 100] and y in [0 100] that I would like
to plot y versus x. However, I would like to have the x and y axes
marked and labeled at the locations of vector components, for example
1, 2, 3, 4, 5, 10, 15, 20, ... on the x axis, preferably preserving
aspect ratio. Function plot systematically divides the axes at equal
intervals 20, 40, 60, 80 and 100. Discrete functions bar and hist
behave similarly. I'm unable to come up with a solution with the
function axis.
All tips are greatly appreciated. Thanks!

--Razmig