Re: removing zero dimensions ...

As you see below, I am not very good at naming functions.. here is a
function i use for the same purpose..

function removeRedundantDimsOf(var)
begin
  var_dims=dimsizes(var)
  dim_names=getvardims(var)
  new_indcs=ind(var_dims.gt.1)
  newdims=var_dims(new_indcs)
  new_dimnames=(dim_names(new_indcs))
  ndims=dimsizes(newdims)
  newvar=new(newdims,typeof(var))
  newvar=var
  do i=0,ndims-1
    newvar!i=new_dimnames(i)
  end do
return(newvar)
end

function remove_redundant_dims_of(var)
begin
  return(removeRedundantDimsOf(var))
end

function remove_empty_dims_of(var)
begin
  return(removeRedundantDimsOf(var))
end

saji

On Thu, Jun 2, 2011 at 4:33 AM, <Maurice.McHugh@noaa.gov> wrote:
> I have used the following successfully.  ncwa is a netCDF operators, and part of the NCO package.
>
>
> ncwa –a z_t fileIn.nc fileOut.nc
>
> where z_t is the vestigial or degenerate dimension of size 1 to be removed from fileIn.
>
> Hope this helps!
>
> Maurice
>
> ----- Original Message -----
> From: Mary Haley <haley@ucar.edu>
> Date: Wednesday, June 1, 2011 2:30 pm
> Subject: Re: removing zero dimensions ...
> To: ncl forum <ncl-talk@ucar.edu>
>
>
>> Just to answer Ufuk's original question:  we don't have any function
>> that removes the "zero dimension" or the "degenerate dimension" as we
>> call it.
>>
>> This question was brought up last year, so here's the answer (and a
>> function) for that:
>>
>>
>>
>> Chad, thanks for contributing your "squeeze" function.
>>
>> --Mary
>>
>>
>> On Jun 1, 2011, at 12:04 PM, Chad Herman wrote:
>>
>> > On 06/01/2011 02:00 PM, ncl-talk-request@ucar.edu wrote:
>> >> Message: 6
>> >> Date: Wed, 01 Jun 2011 11:48:04 +0200
>> >> From: "Ufuk Utku Turuncoglu (BE)"<u.utku.turuncoglu@be.itu.edu.tr>
>> >> Subject: removing zero dimensions ...
>> >> To: NCL USERS<ncl-talk@ucar.edu>
>> >> Message-ID:<4DE60AD4.2010102@be.itu.edu.tr>
>> >> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>> >>
>> >> Hi,
>> >>
>> >> I just wonder that is there any NCL function or procedure (i could
>> not
>> >> find in the documentation) that removes the dimensions that it's actual
>> >> length is one (i call it as zero dimension). For example, i have a
>> 4d
>> >> array and its dimension sizes are "tmp(10, 3, 1, 45)" and i want to
>> >> remove the third dimension and the result array would be "tmp(10,3,45)".
>> >> I actually wrote the following function to do that but i just want
>> to be
>> >> sure it is a generic solution or not
>> >>
>> >> ;---------------------------------------------------------
>> >> ; Removes the zero dimensions from the variable
>> >> ; Input:
>> >> ; data - original data
>> >> ; Output:
>> >> ; tmp  - modified data
>> >> ;---------------------------------------------------------
>> >> undef("rm_empty_dims")
>> >> function rm_empty_dims(data:numeric)
>> >> begin
>> >>    ;--- get dimension size of the data ---
>> >>    dims = dimsizes(data)
>> >>    rank1 = dimsizes(dims)
>> >>
>> >>    ;--- find the indices of the non-zero dimensions ---
>> >>    indx = ind(dims .ne. 1)
>> >>    rank2 = dimsizes(indx)
>> >>
>> >>    ;--- if zero dimension exist, create new data array ---
>> >>    if (rank1 .ne. rank2) then
>> >>      tmp = new(dims(indx), typeof(data))
>> >>      tmp = data
>> >>      return(tmp)
>> >>    else
>> >>      return(data)
>> >>    end if
>> >> end
>> >>
>> >> because, as you can see from the code i could do nothing about
>> >> attributes. How can be sure that result field will have correct
>> >> metadata? May be additional code can be implemented to ensure that.
>> Is
>> >> the "tmp = data" operation safe between variables that are in different
>> >> rank (there could be shifting if it is not safe). Also note that the
>> >> current version of the code is working in my case.
>> >>
>> >> --ufuk
>> >
>> > Ufuk,
>> >
>> > I've written a function ("squeeze") to drop redundant dimensions and
>> retain meta data. (See attached).
>> >
>> > Chad
>> > <squeeze.ncl>_______________________________________________
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Received on Wed Jun 1 20:28:56 2011