Hi Christian,
here is an example
1) reading in the entire chunk:
x = in->T
2) reading in just a slice. assume T is 4D
x = in->T(0,0,:,:) ; here we read in the first time step, the first
level, and all lat,lons using array indexes.
sm
On Thu, 15 Jan 2004, Marquardt, Christian wrote:
> Hello,
>
> I'm more or less new to ncl, so I apologise in advance if I have missed
> the obvious...
>
> I'm reading data from a large grib file which contains several variables
> on multiple levels and for a number of valid times. The usual approach
>
> gribfile = addfile(<filename>)
> data = gribfile-><varname>
>
> works fine, but seems to slurp in the full 4d block of data at once (or
> am I wrong here?). However, I usually only a slice of the full data set
> (say, all times, but a single level only, or a vertical slice, or only
> part of the entire time series, or...). So reading the entire data block
> at once seems to be unnecessary slow; it also requires huge amounts of
> memory.
>
> Is there a way to read only slices of the data? For example, when using
> data in a netCDF from a fortran (or so) program, I could specify the
> start indices in each dimension, etc.
>
> Thanks a lot,
>
> Christian.
>
>
>
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