@nrjank: Yes, this feature request is still valid.  Octave is Matlab-compatible here, i.e., we also produce horizontal labels for the x-axis and y-axis.  Michael's request, and a feature above and beyond Matlab, would be to rotate these labels to be parallel to the axes.

Given that our Qt backend now supports rotation of text objects this should be possible.  But, someone has to be motivated enough to code it.  And as jwe indicated, he would like this to be configurable so that we don't get complaints from Matlab users that the plot is different.

Also see bug #62882 where I provided a patch for implementing xticklabelrotation().  It's not perfect, but should be doable now.

bug #33118 still exists in Octave 4.2.0, but only for fltk and qt toolkits.

This will be hard for the FLTK backend which only supports text rotation in 90 degree increments.

The gnuplot backend supports arbitrary rotation, but unfortunately it seems to work only for text objects and not for xlabels or ylabels.

I'm not opposed to allowing the behavior you want, but I think it should probably be configurable.  I also have no idea how to make the change.  OK to mark as a feature request/wishlist item?

I see the same behvior with gnuplot.

Using mesh() and possibly other 3D plots
the xlabel and ylabel text is horizontal,
not parallel to the respective axes.

Is this a known behavior?
The appropriate orientation is parallel to
each axis.