Re: Re: ut_inv_calendar

Thanks for the routine Carl. With your permission, we may put it
in one of our scripts, like contributed.ncl. Would you be
willing to support it if we get questions?

(You can email me separately on this if you like.)

--Mary

On Mon, 7 Jul 2008, Carl J. Schreck, III wrote:

> As long as we're talking about the ut routines, I'd like to propose another
> function to add to future builds. It takes a time variable and converts it
> from one set of units to another. It only takes a couple lines, but I've
> used it enough that it helped me to make a function for it. I use it when
> I'm overlaying two different datasets that might have different reference
> dates. The code is below in case anyone else would find this useful.
>
> Cheers,
> Carl
>
> function ut_convert( dateFrom:double, unitsFrom:string, unitsTo:string )
> ;******************************************************************************
> ; Converts a time variable from one units to another
> ;
> ; Input variables:
> ; dateFrom: the original date
> ; unitsFrom: the original date units
> ; unitsTo: the NEW date units
> ; Return Value:
> ; retVal: the date converted to its new units
> ;******************************************************************************
>
> local retVal, tempDate, utcDate
>
> begin
> tempDate = dateFrom
> tempDate_at_units = unitsFrom
>
> utcDate = ut_calendar( tempDate, 0 )
>
> retVal = ut_inv_calendar( utcDate(:,0), utcDate(:,1), utcDate(:,2), \\
> utcDate(:,3), utcDate(:,4), utcDate(:,5), \\
> unitsTo, 0 )
>
> return( retVal )
> end
> ;******************************************************************************
>
>
> Mary Haley wrote:
>>
>> The year, month, day, and hour values returned by the internal Udunits
>> routine are all integers to start with, so there's no rounding or
>> truncating going on at the NCL end of things. Only the "seconds"
>> values are returned as float.
>>
>> Now that I think about it, maybe this option '5' should be '-5',
>> since the other negative options return integers...
>>
>> --Mary
>>
>>
>> On Mon, 7 Jul 2008, Dave Allured wrote:
>>
>>> Reading the documentation for ut_calendar, I see that there already are
>>> several other options for specialized result formats. In light of this
>>> and the symmetry issue with ut_inv_calendar, I think it's reasonable to
>>> add option 5 for integers. I would use this option if available. Thanks
>>> to NCL for adding this one.
>>>
>>> For options +2/-2 through +4/-4, YYYYMM etc. as type double or integer,
>>> are the time values rounded or truncated? I suggest that this be added to
>>> the documentation.
>>>
>>> --Dave
>>>
>>> Mary Haley wrote:
>>>>
>>>>
>>>> On Fri, 4 Jul 2008, Mateus Teixeira wrote:
>>>>
>>>>> Thanks Dave,
>>>>>
>>>>> Maybe ut_calendar could have an option equivalent to 0 that returns
>>>>> integers.
>>>>
>>>> In version 5.0.1, ut_calendar will have an "option=5" that is
>>>> identical to option=0, except it returns integers. The seconds
>>>> values will be truncated.
>>>>
>>>> --Mary
>>>>
>>>>> Regards,
>>>>>
>>>>>
>>>>> 2008/7/3 Dave Allured <dave.allured_at_noaa.gov>:
>>>>>
>>>>>> Mateus,
>>>>>>
>>>>>> I think it is usually better to keep unencoded date information as
>>>>>> integers
>>>>>> rather than floats. You can do this in one line when calling
>>>>>> ut_calendar:
>>>>>>
>>>>>> ymd_hms = floattoint (ut_calendar (time, 0))
>>>>>>
>>>>>> Then you do not have to do the multiple reverse conversions for
>>>>>> ut_inv_calendar. HTH.
>>>>>>
>>>>>> Dave Allured
>>>>>> CU/CIRES Climate Diagnostics Center (CDC)
>>>>>> http://cires.colorado.edu/science/centers/cdc/
>>>>>> NOAA/ESRL/PSD, Climate Analysis Branch (CAB)
>>>>>> http://www.cdc.noaa.gov/
>>>>>>
>>>>>> Mateus Teixeira wrote:
>>>>>>
>>>>>>> Dear NCL developers,
>>>>>>>
>>>>>>> Is it possible modify ut_inv_calendar arguments to numerical type?
>>>>>>>
>>>>>>> Sometimes is necessary to convert a set of dates from one time unit to
>>>>>>> another time unit.
>>>>>>> Since ut_calendar with 0 option returns float, it would avoid the
>>>>>>> float to
>>>>>>> integer conversion to put their information into ut_inv_calendar.
>>>>>>>
>>>>>>> Regards,
>>>>>>>
>>>>>>> --
>>>>>>> Mateus da Silva Teixeira
>>>>>>> Meteorologista
>>>>>>> Instituto de Pesquisas Meteorol?gicas - IPMET (www.ipmet.unesp.br <
>>>>>>> http://www.ipmet.unesp.br>)
>>>>>>> Universidade Estadual Paulista - UNESP (www.unesp.br
>>>>>>> <http://www.unesp.br
>>>>>>>> )
>>>>>>> Bauru, SP
>>>>>>>
>>>>>>> Registered Linux User #466740
>>> _______________________________________________
>>> ncl-talk mailing list
>>> ncl-talk_at_ucar.edu
>>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>>>
>>
>> ------------------------------------------------------------------------
>>
>> _______________________________________________
>> ncl-talk mailing list
>> ncl-talk_at_ucar.edu
>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>
> _______________________________________________
> ncl-talk mailing list
> ncl-talk_at_ucar.edu
> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>
_______________________________________________
ncl-talk mailing list
ncl-talk_at_ucar.edu
http://mailman.ucar.edu/mailman/listinfo/ncl-talk
Received on Wed Jul 09 2008 - 09:13:05 MDT