Re: monthly minimum in a yearly time series

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

Hi Francois,
You can use the regridding transform @MIN. Define a yearly time axis, 
and regrid to it using @MIN. The result will be the minimum value in 
each year.  Define the yearly axis so the grid cells start at the 
beginning of each year. An easy way to do this is with the /EDGES qualifier.

   DEFINE/AXIS/EDGES/t="1-jan-1955":1-jan-2000":1/units=year  tyear
   LET minyear = my_var[gt=tyear@MIN]

See "minimum, @MIN regridding" for a discussion of @MIN regridding in 
the Users Guide.

Ansley

DELCLAUX Francois wrote:

> Hi Ferret users,
>
> I have a 45 year time series of monthly values .
> I would like to get the monthly minimum for each year, ie 45 minimum 
> values.
> What is the best way to do this operation ?
> Thanks in advance