No subject

###
min(expr, dim1, dim2 <,tinc>)

Returns the minimum of expr over the specified dimension range. If the
specified dimension is time, an optional time increment tincr may be
specified.


expr    - any valid GrADS expression
dim1    - the starting dimension expression
dim2    - the ending dimension expression
tinc    - optional time increment

dim1 and dim2 are standard GrADS dimension expressions whose dimensions must
match.
###
So, if you're looking for the abs min of your 4 variables tmean.xx, then
your expression min(tmean.62,tmean.63,tmean.64,tmean.66) doesn't look quite
right to me.
Infact the function min() is useful at looking for a relative minimum of an
expression between boundaries dim1 and dim2.
If you want to compare 4 expressions for the minimum between them, than I
would use a nested "if" statement.
Also, are you really sure you have got 66 files open?





> -----Messaggio originale-----
> Da: GRADSUSR at LIST.CINECA.IT [mailto:GRADSUSR at LIST.CINECA.IT] Per conto di
> bernd.becker at METOFFICE.GOV.UK
> Inviato: lunedì 6 agosto 2007 10.37
> A: GRADSUSR at LIST.CINECA.IT
> Oggetto: Re: [GRADSUSR] R: [GRADSUSR] compare 4 timeseries
>
> Mandelli,
> this all makes perfect sense:
>
> The data has an arbitrarily set year 23648.
> The four file contain the 6 hourly climatology,
> each holding one of the 4 daily 6 hourly assimilation cycles.
>
> A single point in this example is as good anything here.
>
> The question is:
>
> how do you get the maximum/minimum value from a set of 4 numbers,
> each from a different file at all x,y,z, and days?
>
> Thanks.
>
> Brute force comparison using scripting may be the only way forward,
> but I am still hopeful, because grads has proved to be so very
> resourceful.
>
> Cheers,
> Bernd.
>
>
> On Fri, 2007-08-03 at 17:37 +0200, Mandelli Alessandro wrote:
> > > -----Messaggio originale-----
> > > Da: GRADSUSR at LIST.CINECA.IT [mailto:GRADSUSR at LIST.CINECA.IT] Per conto
> di
> > > bernd.becker at METOFFICE.GOV.UK
> > > Inviato: venerdì 3 agosto 2007 17.17
> > > A: GRADSUSR at LIST.CINECA.IT
> > > Oggetto: [GRADSUSR] compare 4 timeseries
> >
> >
> > > define t=tloop(min(tmean.62,tmean.63,tmean.64,tmean.66))
> >
> > Are you sure about 66? Maybe it's a typo, maybe not.... 62, 63, 64, 65?
> >
> > > T is varying   Time = 00Z01JAN25655 to 00Z22DEC25655  T = 1 to 356
> >
> > The time series is 23648 years ahead of now. Does it sound ok for you?
> >
> > And if
> > X is fixed     Lon = -97  X = -96
> > Y is fixed     Lat = 33  Y = 124
> > Z is fixed     Lev = 1  Z = 1
> >
> > This looks like a single point in space. Does it sound ok for you?
> --
> Bernd Becker   The Monthly Outlook
> Met Office  FitzRoy Road  Exeter   Devon EX1 3PB  United Kingdom
> Tel.: +44 (0) 1392 884511 Fax: +44 (0)870 900 5050
> E-mail:bernd.becker at metoffice.gov.uk -  http://www.metoffice.gov.uk