> On Wed, Dec 31, 2008 at 08:35:06AM +0100, Arjen Markus wrote: >> > >> > I would change the Tcl version to match the C logic (and the logic for >> the >> > other languages as well) which (as you noted) does use integers for >> the >> > theta-related variables for exactly the rounding reasons you >> mentioned. >> > >> >> Which is what I have done in my private copy. I have not had a chance >> to test these and other changes yet, but I will in the coming few days. > > Arjen, > > Just for the record, your changes make no difference to me. This is on > Ubuntu Hardy x86 32-bit with tcl 8.4. I still have rounding differences > for examples 3, 11 and 20 as before. I can't test example 21 as it is > not enable with tcl 8.4. Will try to upgrade to tcl 8.5 and test again. >
I should have mentioned I have been doing these tests with Tcl 8.5. The difference between Tcl 8.4 and Tcl 8.5 that is of importance here is that in 8.5 the parameter that determines the precision for converting numbers to strings (tcl_precision) is set to 17 by default, making an exact reconversion possible. (The Tcl interface still uses the old string-based mechanism, hence tcl_precision is important. I intend to change that to the Tcl_Obj mechanism.) Example 11 shows very small differences: several numbers like 2384 instead of 2383 in the PostScript output. Perhaps I can get rid of these too, but I gave priority to the others (examples 15 and 16 are fine then?). I will have a look at example 3. It is a new one to me. Example 20 is causing me a slight headache :(. I have checked just about everything I could think of: - All expressions are braced - The file is read correctly - all values are identical to the values I see in the C example - The PostScript file differs in the way the gray colour is determined, but I have not been able to determine why that would be the case. plscmap1n and plscmap1l are called with identical arguments. I will have to descent further into the library functions to determine the cause. Regards, Arjen ------------------------------------------------------------------------------ _______________________________________________ Plplot-devel mailing list Plplot-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/plplot-devel
