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Hi, Yes, your understanding is correct, the output from ncdump has the last dimension (lon) varying most rapidly and the first dimension (time) varying most slowly. The CDL notation that ncdump outputs, which is just a text representation of the binary data in a netCDF file, uses row-major order (last index varying fastest) like C and Java do rather than column major order (first index varying most rapidly) like Fortran and Ruby use. The lat/lon coordinates and are also in the ncdump output: $ ncdump precip.mon.ltm.nc | head -200 netcdf precip.mon.ltm { dimensions: lon = 144 ; lat = 72 ; time = UNLIMITED ; // (12 currently) variables: float lat(lat) ; lat:units = "degrees_north" ; lat:actual_range = 88.75f, -88.75f ; lat:long_name = "Latitude" ; float lon(lon) ; lon:units = "degrees_east" ; lon:long_name = "Longitude" ; lon:actual_range = 1.25f, 358.75f ; double time(time) ; time:units = "hours since 1-1-1 00:00:0.0" ; time:long_name = "Time" ; time:delta_t = "0000-01-00 00:00:00" ; time:actual_range = 0., 8016. ; time:avg_period = "0000-01-00 00:00:00" ; time:ltm_range = 17338824., 17530944. ; float precip(time, lat, lon) ; precip:long_name = "Average Monthly Rate of Precipitation" ; precip:valid_range = 0.f, 70.f ; precip:units = "mm/day" ; precip:add_offset = 0.f ; precip:scale_factor = 1.f ; precip:actual_range = 0.f, 21.89647f ; precip:missing_value = -9.96921e+36f ; precip:precision = 32767s ; precip:least_significant_digit = 2s ; precip:var_desc = "Precipitation" ; precip:dataset = "CPC Merged Analysis of Precipitation Enhanced" ; precip:level_desc = "Surface" ; precip:statistic = "Mean" ; precip:parent_stat = "Mean" ; // global attributes: :Conventions = "COARDS" ; :title = "CPC Merged Analysis of Precipitation (excludes NCEP Reanalysis)" ; :history = "created 03/2002 by CASData version v207\n", "" ; :platform = "Analyses" ; :source = "ftp ftp.cpc.ncep.noaa.gov precip/cmap/monthly" ; :documentation = "http://www.cdc.noaa.gov/cdc/data.cmap.html" ; data: lat = 88.75, 86.25, 83.75, 81.25, 78.75, 76.25, 73.75, 71.25, 68.75, 66.25, 63.75, 61.25, 58.75, 56.25, 53.75, 51.25, 48.75, 46.25, 43.75, 41.25, 38.75, 36.25, 33.75, 31.25, 28.75, 26.25, 23.75, 21.25, 18.75, 16.25, 13.75, 11.25, 8.75, 6.25, 3.75, 1.25, -1.25, -3.75, -6.25, -8.75, -11.25, -13.75, -16.25, -18.75, -21.25, -23.75, -26.25, -28.75, -31.25, -33.75, -36.25, -38.75, -41.25, -43.75, -46.25, -48.75, -51.25, -53.75, -56.25, -58.75, -61.25, -63.75, -66.25, -68.75, -71.25, -73.75, -76.25, -78.75, -81.25, -83.75, -86.25, -88.75 ; lon = 1.25, 3.75, 6.25, 8.75, 11.25, 13.75, 16.25, 18.75, 21.25, 23.75, 26.25, 28.75, 31.25, 33.75, 36.25, 38.75, 41.25, 43.75, 46.25, 48.75, 51.25, 53.75, 56.25, 58.75, 61.25, 63.75, 66.25, 68.75, 71.25, 73.75, 76.25, 78.75, 81.25, 83.75, 86.25, 88.75, 91.25, 93.75, 96.25, 98.75, 101.25, 103.75, 106.25, 108.75, 111.25, 113.75, 116.25, 118.75, 121.25, 123.75, 126.25, 128.75, 131.25, 133.75, 136.25, 138.75, 141.25, 143.75, 146.25, 148.75, 151.25, 153.75, 156.25, 158.75, 161.25, 163.75, 166.25, 168.75, 171.25, 173.75, 176.25, 178.75, 181.25, 183.75, 186.25, 188.75, 191.25, 193.75, 196.25, 198.75, 201.25, 203.75, 206.25, 208.75, 211.25, 213.75, 216.25, 218.75, 221.25, 223.75, 226.25, 228.75, 231.25, 233.75, 236.25, 238.75, 241.25, 243.75, 246.25, 248.75, 251.25, 253.75, 256.25, 258.75, 261.25, 263.75, 266.25, 268.75, 271.25, 273.75, 276.25, 278.75, 281.25, 283.75, 286.25, 288.75, 291.25, 293.75, 296.25, 298.75, 301.25, 303.75, 306.25, 308.75, 311.25, 313.75, 316.25, 318.75, 321.25, 323.75, 326.25, 328.75, 331.25, 333.75, 336.25, 338.75, 341.25, 343.75, 346.25, 348.75, 351.25, 353.75, 356.25, 358.75 ; time = 0, 744, 1416, 2160, 2880, 3624, 4344, 5088, 5832, 6552, 7296, 8016 ; precip = 0.2890909, 0.2954545, 0.2918182, 0.29, 0.2886364, 0.2890909, 0.2886364, 0.2872727, 0.2890909, 0.2913636, 0.2895454, 0.2895454, 0.2913636, 0.2940909, 0.2954545, 0.2986363, 0.3, 0.3036364, 0.3072727, 0.3118182, 0.3168182, 0.3231818, 0.3368182, 0.3490909, 0.3586363, 0.3704545, 0.3854545, 0.4031818, 0.4236364, 0.4454545, 0.4695455, 0.4936364, 0.5186363, 0.5454546, 0.5722727, 0.6018182, 0.6277273, 0.6518182, ... --Russ Russ Rew UCAR Unidata Program address@hidden http://www.unidata.ucar.edu Ticket Details =================== Ticket ID: SCT-388171 Department: Support netCDF Priority: Normal Status: Closed