Re: Ambiguous coordinates on time axis

[Ansley Manke <ansley.b.manke@xxxxxxxx>]

Hi David,
Actually, I think I was wrong in saying that your Approach 1 just computes
the average over one year for both variables. The calculation is done 
correctly,
over 1 year for the first dataset and 4 years for the second dataset.  
The ambiguous
coordinates warning just lets you know you have done two different averages.

The difference you're seeing with approach 2 may be due to a difference 
in the
exact range used between the calculation of  the average using all 
values in L for
each dataset, and a specific range of values in time.  @AVE uses a weighted
averaging scheme, and so if the edges of the regions are different you could
see a different result.  When you turn on MODE DIAGNOSTIC, do the dates
specified in the calculation of the result in Approach 1 match the dates 
you are
specifying in Approach 2?

Ansley


David Muhati wrote:

> Hi all,
> Came across this error message while calculating the difference 
> between myvar (variable) for 2 different periods for 1 year and 4years 
> respectively. Not sure what the best approach is of this two; NB: d=1 
> is the 1year period e.g 1997 and d=2 is the 4 year (1995 to 1998)
> Approach 1
> yes? fill myvar[d=1,l=@ave]- myvar[d=2,l=@ave]
> yes? go land
> error: ambiguous coordinates on time axis
> Approach 2
> yes? fill myvar[d=1,t="1-jan-1997":"31-dec-1997"@ave]- 
> myvar[d=2,t="1-jan-1995":"31-dec-1998"@ave]
> yes? go land
> Doesn't give an error message.
>
> So which is the best because the results of the two look different?
> David