From: Michael B. B. <be...@cr...> - 2002-10-08 16:51:18
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When I'm using large integer values, like, say, a bunch of 32-bit time_t (effectively a positive 32 bit integer), for the values of x, the rendering for the tick marks and labels go wonky: they're very wide and the tick spacing is not close to uniform. The diff of the high and low values typically will be well less than 100,000. Is there a canonical workaround to deal with rendering precision caused by this apparent stretching of precision? |
From: Maurice L. <mj...@ga...> - 2002-10-12 11:14:58
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Michael Brian Bentley writes: > When I'm using large integer values, like, say, a bunch of 32-bit > time_t (effectively a positive 32 bit integer), for the values of x, > the rendering for the tick marks and labels go wonky: they're very > wide and the tick spacing is not close to uniform. The diff of the > high and low values typically will be well less than 100,000. Is > there a canonical workaround to deal with rendering precision caused > by this apparent stretching of precision? PLplot does have some precision problems, e.g. the devices are limited to a 16 bit address space. Usually this isn't a problem because physical plotting devices are similarly limited in resolution -- it comes up only (AFAIK) when zooming at high magnification. There is some work underway to eventually eliminate this problem but it will take some time. However this doesn't sound like the problem you are having. It might be a bug.. if you could submit a test case that illustrates the problem (in whatever language binding suits you), that would help. -- Maurice LeBrun mj...@ga... Research Organization for Information Science and Technology of Japan (RIST) |
From: Alan W. I. <ir...@be...> - 2002-10-12 14:00:25
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On Sat, 12 Oct 2002, Maurice LeBrun wrote: > Michael Brian Bentley writes: > > When I'm using large integer values, like, say, a bunch of 32-bit > > PLplot does have some precision problems > [but] this doesn't sound like the problem you are having. I took the discussion off-list, but my apologies for not giving the conclusion here. Since I couldn't replicate his specific problem, Michael concluded it was due to one or more of the many changes he had made to his personal version of PLplot to get it to work with OpenGL. I don't believe such widespread changes should be necessary since one of our other users (Gary Bishop) has apparently got PLplot to work under OpenGL without such changes. However, I cannot say absolutely for sure because I don't have access to the OpenGL part of Gary's code at this time. Alan |