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Christine, >Date: Fri, 25 Feb 2005 14:10:11 -0600 >From: Christine Molling <address@hidden> >Organization: UCAR/Unidata >To: Steve Emmerson <address@hidden>, >To: Tom Whittaker <address@hidden> >Subject: Re: [Fwd: Re: [Fwd: UTM file]] The above message contained the following: > What am I trying to accomplish? Merely express time in units that have > a one-to-one relationship with calendar time. Good luck. Units of the physical quantity "time" don't have a simple, one-to-one relationship with calendar time. Believe me, I've beaten my head against this issure more times than I can remember. > I'm developing precision > agriculture software in which events happen on specific days (I use days > since yyyy-mm-dd), and in which some quantities may only be applicable > to a year, such as yield, or accumulated drainage. For those I use > 'year', because the quantity is not associated with any one particular > day. I can forsee some situation where two different persons get some > model output and their converted values are different because of the > average vs exact number of days per year issue. > > I understand that the Udunits folks might not want to tackle converting > our "strange" calendar's years or months to days. Right. That's outside the scope of the UDUNITS package, which was designed to handle units of physical quantities only. > Although now that I > think about it, doesn't everybody (at least in the Atmos Sci community) > have that same data table of number-of-days-per-month in at least one of > their programs? Unless there is concern about code bloat in Udunits, > why not stick calendar conversions in there for commonly used calendars? > Everyone would love to have it in there, I'm sure. No doubt. Unfortunately, it's non-trivial, would easily double the size of the package, doesn't have any standards, and would consume time I don't have. What we need is a freely-available calendar package for C and Fortran. If you know of one, then use it and let me know about it. Regards, Steve Emmerson