Importing a string from NCDF4 file with IDL

Question

I am new to IDL

I am importing data from an NCDF4 into IDL. All the variables that are numeric import perfectly. However station name comes in as an array of 200. An example of the output is :-

84 82 69 76 69 87 95 65 69 82 79 32 32 32 0 0 0 0 0 0 0 0 .

etc.

I never experienced this problem with R. I tried using a string command but that won't work for. If I comment out the string command, the rest of the script work perfectly. My script is below

  PRO Lat_Lon_Alt_Array                              

; This program is the extract the Latitute, Longigitude & Altitute
; with the Site name and file code. 
; The purpose is to output the above dimensions from the station files
; into a csv file.

COMPILE_OPt IDL2

the_file_list = file_search('D:/Rwork/Project/25_Files/','*.nc')

;---------------------------------------------------------------
n_files=N_Elements(the_file_list)  
station_name_st=string(n_files)                              ; try this
latitude_arr=DBLARR(n_files)
longitude_arr=DBLARR(n_files)
height_arr=DBLARR(n_files)

;----------------------------------------------------------------

FOR filein =  0, N_ElEMENTS (the_file_list)-1 DO BEGIN



 station = NCDF_OPEN(the_file_list[filein])

 ;fred= NCDF_VARINQ(station,station_name)

 NCDF_VARGET, station, 'station_name', station_name           
 NCDF_VARGET, station, 'lat', latitude
 NCDF_VARGET, station, 'lon', longitude
 NCDF_VARGET, station, 'alt', height

 stop
 ;-------------------------------------------------------
 ;station_name_st[filein]=station_name
 latitude_arr[filein]=latitude
 longitude_arr[filein]=longitude
 height_arr[filein]=height
 ;-----------------------------------------------------

 Print,the_file_list[filein]
 Print, 'station_name'
 Print, station_name
 Print,'lat'
 Print,latitude
 Print,'lon'
 print,longitude
 Print,'alt'
 Print,height


 HEADER=['File_Address','Latitude','Longitude','Altitude']

 ENDFOR

 WRITE_CSV,   'LatLon.csv',the_file_list,latitude_arr,longitude_arr,height_arr,$
 HEADER=HEADER,TABLE_HEADER='LAT,LON & ALT OF STATIONS'

 RETURN
 END

Answer 1

In some instances, NetCDF files store "strings" as byte arrays. Your station_name variable appears to be one of these cases. You just need to use the STRING function to convert station_name after reading it in with the NCDF_VARGET procedure.

NCDF_VARGET, station, 'station_name', station_name
PRINT, station_name

84 82 69 76 69 87 95 65 69 82 79 32 32 32 0 0 0 0 0 0 0 0

station_name = STRING(station_name)
PRINT, station_name

TRELEW_AERO