[pstricks] How do xAxisLabelPos and yAxisLabelPos work?

[Denis Bitouzé]

Hello,

I try to place xAxisLabel and yAxisLabel at right positions playing with
xAxisLabelPos and yAxisLabelPos but I definitively don't understand how
they work.

Is there a place where this is explained? The (nice) pstricks-add
documentation only shows examples...

Thanks.
-- 
Denis