I am very new with netcdf file. And currently have to extract the data from such netcdf which looks like below:

8 variables (excluding dimension variables):
        double time_bnds[bnds,time]      
        int rotated_latitude_longitude[]   
                grid_mapping_name: rotated_latitude_longitude
                grid_north_pole_latitude: 39.25
                grid_north_pole_longitude: -162
                north_pole_grid_longitude: 0
            float lat[rlon,rlat]   
                standard_name: latitude
                long_name: latitude coordinate
                units: degrees_north
                bounds: lat_vertices
            float lon[rlon,rlat]   
                standard_name: longitude
                long_name: longitude coordinate
                units: degrees_east
                bounds: lon_vertices
            float lat_vertices[vertices,rlon,rlat]   
                units: degrees_north
            float lon_vertices[vertices,rlon,rlat]   
                units: degrees_east
            double height[]   
                units: m
                axis: Z
                positive: up
                long_name: height
                standard_name: height
            float tasmax[rlon,rlat,time]   
                standard_name: air_temperature
                long_name: Daily Maximum Near-Surface Air Temperature
                comment: daily-maximum near-surface (usually, 2 meter) air temperature.
                units: K
                cell_methods: time: maximum
                history: 2015-05-06T15:11:26Z altered by CMOR: Treated scalar dimension: 'height'. 2015-05-06T15:11:26Z altered by CMOR: replaced missing value flag (-1e+20) with standard missing value (1e+20).
                coordinates: height lat lon
                missing_value: 1.00000002004088e+20
                _FillValue: 1.00000002004088e+20
                associated_files: gridspecFile: gridspec_atmos_fx_MPI-CSC-REMO2009_rcp45_r0i0p0.nc
                grid_mapping: rotated_latitude_longitude

5 dimensions:
        time  Size:1825   *** is unlimited ***
            bounds: time_bnds
            units: days since 1949-12-01T00:00:00Z
            calendar: proleptic_gregorian
            axis: T
            long_name: time
            standard_name: time
        rlat  Size:103
            units: degrees
            axis: Y
            long_name: latitude in rotated pole grid
            standard_name: grid_latitude
        rlon  Size:106
            units: degrees
            axis: X
            long_name: longitude in rotated pole grid
            standard_name: grid_longitude
        bnds  Size:2
        vertices  Size:4

Although, there are many explanation of different netcdf files but I found my situation is a bit complicated in terms of number of variables and dimensions. Here I am confused with float lat[rlon,rlat]; why rlon and rlat is here with normal latitude? Similarly with the case of float lon[rlon,rlat]. And why rlon and rlat separately present in dimensions also?

Eventually I need to extract the temperature with geographical coordinates (latitude North and longitude East).

closed as too broad by whyzar, BERA, aldo_tapia, xunilk, Ian Turton Mar 6 '18 at 17:51

Please edit the question to limit it to a specific problem with enough detail to identify an adequate answer. Avoid asking multiple distinct questions at once. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

  • Which software are you using? It's too broad your question – aldo_tapia Mar 6 '18 at 14:27
  • I am using R package ncdf4. Yes its too broad, because I am unable to understand this complex data. Every previous post has simple data explanation. – kashiff007 Mar 6 '18 at 15:51
  • Use library(raster); library(ncdf); raster('path/to/file.nc', varname='tasmax') – aldo_tapia Mar 6 '18 at 18:07