BTW, 1_133_395_200.0 is the number of seconds since January 1, 1970. Not sure why the comment in the C code for example 29 mentions 1900. Jerry
On Jul 10, 2008, at 2:57 PM, Alan W. Irwin wrote: > Hi Andrew: > > Jerry's recent commit message for Ada example 29 inspired me to > investigate > further, and indeed the fortran (and presumably the rest of the non-C) > examples are an hour out compared to the C example. > > For example, in python > > calendar.timegm((2005,12,1,0,0,0)) > > returns > > 1133395200 > > which is consistent with Jerry's recent fix for the Ada example, but > an hour inconsistent with > > f77/x29f.fm4: tstart = 1133398800 > f95/x29f.f90: tstart = 1133398800 > java/x29.java: tstart = 1133398800; > > > Part of the problem here is the time code in example 29 is just too > complicated. mktime has a local timezone offset which must be > compensated by > the offset logic which is difficult to follow without doing a lot > of man > reading. I think that logic is actually working and only the > constants in > the non-C examples are out by an hour (as shown above), but to > clear up all > confusion I suggest we make the time code in the C example 29 much > simpler > by working with UTC from the start. The way to do that is to use > the POSIX > equivalent of the Linux timegm function (written in terms of mktime > and > tzset, see the Linux timegm man page) for maximum portability. > > Also, for the python example we should directly use calendar.timegm > (as > above). There might be something equivalent to timegm in java as > well. > > Andrew, if you agree to the above straightforward changes I should > be able > to do them (except for finding a timegm equivalent in java) myself. > > Alan > __________________________ > Alan W. Irwin > > Astronomical research affiliation with Department of Physics and > Astronomy, > University of Victoria (astrowww.phys.uvic.ca). > > Programming affiliations with the FreeEOS equation-of-state > implementation > for stellar interiors (freeeos.sf.net); PLplot scientific plotting > software > package (plplot.org); the libLASi project (unifont.org/lasi); the > Loads of > Linux Links project (loll.sf.net); and the Linux Brochure Project > (lbproject.sf.net). > __________________________ > > Linux-powered Science > __________________________ > > ---------------------------------------------------------------------- > --- > Sponsored by: SourceForge.net Community Choice Awards: VOTE NOW! > Studies have shown that voting for your favorite open source project, > along with a healthy diet, reduces your potential for chronic lameness > and boredom. Vote Now at http://www.sourceforge.net/community/cca08 > _______________________________________________ > Plplot-devel mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/plplot-devel > ------------------------------------------------------------------------- Sponsored by: SourceForge.net Community Choice Awards: VOTE NOW! Studies have shown that voting for your favorite open source project, along with a healthy diet, reduces your potential for chronic lameness and boredom. Vote Now at http://www.sourceforge.net/community/cca08 _______________________________________________ Plplot-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/plplot-devel
