From: Andre Wobst <wobsta@us...>  20070806 12:31:39

Hi Michael, On 24.07.07, Michael SCHINDLER wrote: > as you are currently working at the graph module, I would like to make > a suggestion: I often encounter the problem that an axis partitioning > fails (in ydirection) because I am plotting a constant function. As > this occurs when I want to look at some data a script produced, this > is extremely inconvenient. > > What about indroducing another parameter for the axis, some "minmal" > data range  just to make the runs more stable and one does not have > to worry about constant data all the time? I still don't know what to do. It's not the first time somebody complains (and thus maybe I should stop ignoring this completely), but I still don't know how to do better. Technically it's not complicated. But what's a reasonable minimal axis range. 1e10??? Should we really introduce such a "feature"? It looks too application depended to me. You could do even more complicated things (and introducing more paramters). gnuplot for examples does (or at least did at a certain point) a range of 1 when the range was too small (which was easy to produce accidentally due to single precision floats) ... and I never really liked that behaviour eigher. I had the idea of optionally including the zero value at the axis range (and I did even code that in an early PyX version, but this was shut up by others together with the datavmin/vmax and others IIRC). The point with the zero is, that it isn't a good default either (to always include it) and it doesn't help you everywhere (i.e. when your data is always zero, you get the same problem as before ... and on a log axis you need to use 1 instead of zero, which is even more made up out of thin air). The only good thing of this old solution was to have something *independed* of the actuall data you pass to the graph. I would like to have a solution *independed* of the data you pass to the graph. But I really don't see how this could be done ... André  by _ _ _ Dr. André Wobst / \ \ / ) wobsta@..., http://www.wobsta.de/ / _ \ \/\/ / PyX  High quality PostScript and PDF figures (_/ \_)_/\_/ with Python & TeX: visit http://pyx.sourceforge.net/ 