Re: negative years

[Jaison Kurian <jaison@xxxxxxxxxxxxxxxxxx>]

Hi Hein Zelle,
                 I don't think there is a way to specify "BC" in T0. 
Anyway i think the following method will work for you....provided
matlab looks only for the T-values and not for the "T0" in a netcdf
file....(sorry....i don't have any experience with matlab...)..please
correct me if I am wrong.

! define a time axis with T0="01-JAN-0000 00:00:00"

       define axis/t=01-JAN-1900:10-JAN-1900:1/units=days/\
                 T0="01-JAN-0000 00:00:00"  time

! now the T-values on a time axis with T0="00-JAN-0000 00:00:00" will be
!      that of above time axis + 1 ==> since units is "days"

       define axis/t/units=days/T0="01-jan-0000 00:00:00" tmat=t[gt=time]+1

! Let us assume that matlab reads only the T-values (in the assumption
!      that these are Julian Days/Dates based on T0="00-JAN-0000 00:00:00")
!        ==>  only the time data need's to be correct and the "T0 can be
!               wrong"...then regrid the original variable to the second
!               time axis (tmat) using @ASN or RESHAPE ...then you will
!               have proper t-values to be used in matlab
!
!      let matlab_var = original_var[gt=tmat@ASN]


With Regards

Jaison

On Thu, 2 Jun 2005, Hein Zelle wrote:

> I have a silly problem reading Ferret-generated netcdf files in
> Matlab. Matlab uses julian dates (days since 0000) for all it's time
> computations, which works well. However, it defines 0000 as
>
> 00-jan-0000 00:00:00
>
> which doesn't exist! I'm trying to define a time axis in ferret that
> uses Matlab date numbers as values for t, but I'm having trouble
> telling ferret that t0 should be the above date, as Ferret correctly
> notices that the date format is invalid.
>
> Is there a way to specify "31-dec-0001 00:00:00 BC" in Ferret?
>
> Hein Zelle
>
> --
>
> Unix is user friendly. It's just very particular about who
> it's friends are.
>
> Hein Zelle                     hein@icce.rug.nl
> 	                        http://www.icce.rug.nl/~hein
--
___________________________________________________

    Jaison Kurian
    Centre for Atmospheric and Oceanic Sciences
    Indian Institute of Science
    B A N G A L O R E   560 012
    Ph: +91-80-22932505 Extn. 229
        +91-80-23600450
    Fax:+91-80-23600865
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