Mathematica can't Import data of NetCDF file with Datasets name including "."

Question

I have downloaded NetCDF data file EVE_L3_merged_1nm_2015323_005.ncdf from http://lasp.colorado.edu/eve/data_access/evewebdata/products/merged/ and read it by Mathematica 10.0.2 on my windows 7.

Import["D:\\...\\EVE_L3_merged_1nm_2015323_005.ncdf", "Elements"]

gives {"Annotations", "Data", "DataFormat", "Datasets", "Dimensions", "Metadata"}. the "Annotations", "DataFormat",names of "Datasets", "Dimensions", "Metadata" are all Imported correctly and

datsets =Import["D:\\...\\EVE_L3_merged_1nm_2015323_005.ncdf", "Datasets"];
Transpose@{Range@Length@datsets, datsets}

returns

{{1, "PRIMARY"}, {2, "PRIMARY_HEAD"}, {3, "LINESMETA_HEADER"}, {4, 
  "BANDSMETA_HEADER"}, {5, "DIODEMETA_HEADER"}, {6, 
  "SPECTRUMMETA_HEADER"}, {7, "MERGEDDATA_HEADER"}, {8, 
  "LINESMETA.WAVE_CENTER"}, {9, "LINESMETA.WAVE_MIN"}, {10, 
  "LINESMETA.WAVE_MAX"}, {11, "LINESMETA.LOGT"}, {12, 
  "LINESMETA.NAME"}, {13, "LINESMETA.TYPE"}, {14, 
  "LINESMETA.BLENDS"}, {15, "BANDSMETA.NAME"}, {16, 
  "BANDSMETA.TYPE"}, {17, "DIODEMETA.NAME"}, {18, 
  "DIODEMETA.TYPE"}, {19, "SPECTRUMMETA.WAVELENGTH"}, {20, 
  "SPECTRUMMETA.IRRADIANCE_UNITS"}, {21, "MERGEDDATA.YYYYDOY"}, {22, 
  "MERGEDDATA.CAPTURE"}, {23, "MERGEDDATA.SP_IRRADIANCE"}, {24, 
  "MERGEDDATA.SP_STDEV"}, {25, "MERGEDDATA.SP_PRECISION"}, {26, 
  "MERGEDDATA.SP_ACCURACY"}, {27, "MERGEDDATA.BAND_IRRADIANCE"}, {28, 
  "MERGEDDATA.BAND_STDEV"}, {29, "MERGEDDATA.BAND_PRECISION"}, {30, 
  "MERGEDDATA.BAND_ACCURACY"}, {31, 
  "MERGEDDATA.DIODE_IRRADIANCE"}, {32, "MERGEDDATA.DIODE_STDEV"}, {33,
   "MERGEDDATA.DIODE_PRECISION"}, {34, 
  "MERGEDDATA.DIODE_ACCURACY"}, {35, 
  "MERGEDDATA.LINE_IRRADIANCE"}, {36, "MERGEDDATA.LINE_STDEV"}, {37, 
  "MERGEDDATA.LINE_PRECISION"}, {38, "MERGEDDATA.LINE_ACCURACY"}, {39,
   "MERGEDDATA.AU_FACTOR"}}

notice that since 8th quantity the name of dataset contains "." by form "*.*"

If I Import the dataset whose name contains no "." by, for example,

Import["D:\\...\\EVE_L3_merged_1nm_2015323_005.ncdf", {"Datasets", "BANDSMETA_HEADER"}]

Import works well. However if I import dataset whose name contains "." by

Import["D:\\...\\EVE_L3_merged_1nm_2015323_005.ncdf",   {"Datasets", "MERGEDDATA.YYYYDOY"}]

Import broke and suggested

File does not contain a dataset "MERGEDDATA.YYYYDOY"

This problem is not confined to this particular file but occurs every time I Import NetCDF file with Datasets name including ".".

How could I Import data correctly?

Answer 1

So, as we can see here

So if the dataset name contains one of those characters, it needs to be escaped. Try this, replacing "~/Downloads/" with "D:\...\" for the file

elementlist = 
 StringReplace[#, "." -> "\\."] & /@ 
  Import["~/Downloads/EVE_L3_merged_1nm_2015323_005.nc", "Datasets"]
(* {"PRIMARY", "PRIMARY_HEAD", "LINESMETA_HEADER", \
"BANDSMETA_HEADER", "DIODEMETA_HEADER", "SPECTRUMMETA_HEADER", \
"MERGEDDATA_HEADER", "LINESMETA\\.WAVE_CENTER", \
"LINESMETA\\.WAVE_MIN", "LINESMETA\\.WAVE_MAX", "LINESMETA\\.LOGT", \
"LINESMETA\\.NAME", "LINESMETA\\.TYPE", "LINESMETA\\.BLENDS", \
"BANDSMETA\\.NAME", "BANDSMETA\\.TYPE", "DIODEMETA\\.NAME", \
"DIODEMETA\\.TYPE", "SPECTRUMMETA\\.WAVELENGTH", \
"SPECTRUMMETA\\.IRRADIANCE_UNITS", "MERGEDDATA\\.YYYYDOY", \
"MERGEDDATA\\.CAPTURE", "MERGEDDATA\\.SP_IRRADIANCE", \
"MERGEDDATA\\.SP_STDEV", "MERGEDDATA\\.SP_PRECISION", \
"MERGEDDATA\\.SP_ACCURACY", "MERGEDDATA\\.BAND_IRRADIANCE", \
"MERGEDDATA\\.BAND_STDEV", "MERGEDDATA\\.BAND_PRECISION", "MERGEDDATA\
\\.BAND_ACCURACY", "MERGEDDATA\\.DIODE_IRRADIANCE", \
"MERGEDDATA\\.DIODE_STDEV", "MERGEDDATA\\.DIODE_PRECISION", \
"MERGEDDATA\\.DIODE_ACCURACY", "MERGEDDATA\\.LINE_IRRADIANCE", \
"MERGEDDATA\\.LINE_STDEV", "MERGEDDATA\\.LINE_PRECISION", "MERGEDDATA\
\\.LINE_ACCURACY", "MERGEDDATA\\.AU_FACTOR"} *)

data = Import[
     "~/Downloads/EVE_L3_merged_1nm_2015323_005.nc", {"Datasets", #}]& /@ elementlist;

and you can check that everything imported fine by

Dimensions /@ data
(* {{1}, {1, 5}, {1, 53}, {1, 28}, {1, 27}, {1, 47}, {1, 
  90}, {1, 39}, {1, 39}, {1, 39}, {1, 39}, {1, 39}, {1, 39}, {1, 
  39}, {1, 20}, {1, 20}, {1, 6}, {1, 6}, {1, 100}, {1}, {1, 2029}, {1,
   2029}, {1, 2029, 100}, {1, 2029, 100}, {1, 2029, 100}, {1, 2029, 
  100}, {1, 2029, 20}, {1, 2029, 20}, {1, 2029, 20}, {1, 2029, 
  20}, {1, 2029, 6}, {1, 2029, 6}, {1, 2029, 6}, {1, 2029, 6}, {1, 
  2029, 39}, {1, 2029, 39}, {1, 2029, 39}, {1, 2029, 39}, {1, 2029}} *)

This only works with periods, I wish there were a more robust way of treating the strings literally without escape characters, or a way of replacing them automatically. Like when you past some text into a string, it asks you if you want to escape the characters.

Anyway, this is a usable workaround for your problem.

Answer 2

The issue has been fixed in V13.0 and no workarounds are needed:

In[2]:= Import["EVE_L3_merged_1nm_2022095_007.ncdf","/MERGEDDATA.YYYYDOY"]

Out[2]= NumericArray[<1,4353>, Integer32]