[ncl-talk] Averaging over time dimension
Soma Roy
somaroy892 at gmail.com
Thu Mar 8 12:52:50 MST 2018
Thank you Adam Phillips.
I will check this. Another way I think, using CDO first 'split' time steps
or 'timmean' entire file then perform the operations over different
variables in NCL.
Soma
On Mar 9, 2018 01:15, "Adam Phillips" <asphilli at ucar.edu> wrote:
> Hi Soma,
> Please remember to always respond to the ncl-talk email list when
> responding. That way others can assist and can also see the answers to
> queries.
>
> Your emailed reply stated:
> > How much space is then required to process all the variables in single
> run? I am using NCL in my laptop (i5 with 8GB ram)and free space in that
> drive is 86 GB.
>
> I cannot answer that question precisely. Your machine will be using part
> of its' memory for core functionality and other tasks. What you can do is
> to try to conserve memory in your script as best as you can. The sample
> coding snippets I sent you will assist in that task. Try what I suggested
> and let ncl-talk know if you have further issues. Note that beyond what I
> stated in my original reply, another avenue you might have to take to save
> memory is to read in the variables in different scripts.
> Adam
>
>
> On Thu, Mar 8, 2018 at 8:35 AM, Soma Roy <somaroy892 at gmail.com> wrote:
>
>> Hi,
>>
>> I am trying to access multiple variables from a file and need to average
>> over time for each variables.
>>
>> I am running the following codes:
>>
>> fn = "ERA_Plev.nc" ; define filename
>> in = addfile(fn,"r") ; open netcdf file
>> printVarSummary(in)
>>
>> T=in->t ; temperature
>> U=in->u ; U wind
>> V=in->v ; V wind
>>
>> printVarSummary(T)
>> printVarSummary(U)
>> printVarSummary(V)
>>
>> ;T1 = dim_avg_n(T,0)
>> ;T at units = "K"
>> end
>>
>> Summary of the file is like below;
>>
>> Variable: in
>> Type: file
>> File path: ERA_Plev.nc
>> Number of global attributes: 2
>> Number of dimensions: 4
>> Number of variables: 18
>> fatal:NclMalloc Failed:[errno=12]
>> Segmentation fault (core dumped)
>>
>> When I am calling only Temperature using the codes below;
>>
>> fn = "ERA_Plev.nc" ; define filename
>> in = addfile(fn,"r") ; open netcdf file
>> printVarSummary(in)
>>
>> T=in->t ; temperature
>> ;U=in->u ; U wind
>> ;V=in->v ; V wind
>>
>> printVarSummary(T)
>> ;printVarSummary(U)
>> ;printVarSummary(V)
>>
>> ;T1 = dim_avg_n(T,0)
>> ;T at units = "K"
>> end
>>
>> It shows
>>
>> Variable: T
>> Type: short
>> Total Size: 1042566000 bytes
>> 521283000 values
>> Number of Dimensions: 4
>> Dimensions and sizes: [time | 120] x [level | 25] x [latitude | 721] x
>> [longitude | 241]
>> Coordinates:
>> time: [994176..994890]
>> level: [50..125]
>> latitude: [90..-90]
>> longitude: [60..120]
>> Number Of Attributes: 7
>> scale_factor : 0.00218919045579553
>> add_offset : 252.4797479951041
>> _FillValue : -32767
>> missing_value : -32767
>> units : K
>> long_name : Temperature
>> standard_name : air_temperature
>>
>>
>> I have to call several other variables from this file (14 GB) and I need
>> to average over time such that 'Dimensions' of each variables will be like
>> below;
>>
>> [time | 1]* [level | 25] x [latitude | 721] x [longitude | 241]
>>
>> Which function I have to use in this case?
>>
>>
>> When I am trying to call other variables from the file I am getting the
>> error message as;
>>
>> Variable: in
>> Type: file
>> File path: ERA_Plev.nc
>> Number of global attributes: 2
>> Number of dimensions: 4
>> Number of variables: 18
>> fatal:NclMalloc Failed:[errno=12]
>> Segmentation fault (core dumped)
>>
>> Please kindly inform me how to resolve this issue.
>>
>>
>> Thank you,
>> Soma
>>
>>
>>
>> _______________________________________________
>> ncl-talk mailing list
>> ncl-talk at ucar.edu
>> List instructions, subscriber options, unsubscribe:
>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>>
>>
>
>
> --
> Adam Phillips
> Associate Scientist, Climate and Global Dynamics Laboratory, NCAR
> www.cgd.ucar.edu/staff/asphilli/ 303-497-1726
>
> <http://www.cgd.ucar.edu/staff/asphilli>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.ucar.edu/pipermail/ncl-talk/attachments/20180309/a0ccba42/attachment.html>
More information about the ncl-talk
mailing list