[netcdfgroup] Question about slicing from variable values, not index?

• To: <netcdfgroup@xxxxxxxxxxxxxxxx>
• Subject: [netcdfgroup] Question about slicing from variable values, not index?
• From: "demail" <demail973@xxxxxxxxxx>
• Date: Thu, 1 Apr 2010 21:35:25 -0400

Question about slicing from variable values, not index?

using:  
netCDF4-0.9.win32-py2.6.exe
numpy-1.3.0-py2.6

#This works:
rootgrp = Dataset(NC_FIL, 'w', format='NETCDF4')
rootgrp.createDimension('lat', 5)
rootgrp.createDimension('lon', 5)
dogs = rootgrp.createVariable('dogs','u1',('lat','lon'))
latitudes = rootgrp.createVariable('latitude','f4',('lat',))
longitudes = rootgrp.createVariable('longitude','f4',('lon',))
lats =  numpy.arange(35,36,.2) #lats = array([ 35. ,  35.2,  35.4,  35.6,
35.8])
lons =  numpy.arange(82,83,.2) #lons = array([ 82. ,  82.2,  82.4,  82.6,
82.8])
latitudes[:] = lats
longitudes[:] = lons
dogs[:] = NumPy_2dArray #NumPy 2 d array, number of dogs at lat / lon (5 x
5)  
rootgrp.close()

#Can get results:
getrootgrp = Dataset(NC_FIL, 'r', format='NETCDF4')
temp_dogs = getrootgrp.variables['dogs'][:]
temp_lat= getrootgrp.variables['latitude'][:]
temp_lon = getrootgrp.variables['longitude'][:]

OK: I want to be able to perform a slice from
getrootgrp.variables['latitude'] and getrootgrp.variables['longitude'],
based on value, not index, 
that will return array [latitude, latitude, number of dogs].

Conceptually, I am thinking along the lines of Coordinate Variables or array
subscripting, but have not been successful in using it to have something
like:
temp_lat_lon_dogs = getrootgrp.variables['dogs'][:], latitude[35.2:35.8],
longitude >  82.2]

• Follow-Ups:
  • Re: [netcdfgroup] Question about slicing from variable values, not index?
    • From: Jeff Whitaker