PRO VIIRS_GEO_READ, FILE, LAT, LON, ZEN

;- Read a VIIRS GEO HDF5 file (M band)

;- Check arguments
if (n_elements(file) eq 0) then message, 'Argument FILE is undefined'
 
;- Parse the filename
result = strsplit(file_basename(file), '_', /extract)
product = result[0]
satname = result[1]
date    = result[2]
begtime = result[3]
endtime = result[4]

;- Open the file
file_id = h5f_open(file)

;- Set the group name
group_name = '/All_Data/VIIRS-MOD-GEO-TC_All'

;- Read the latitude data
dataset_name = 'Latitude'
data_id = h5d_open(file_id, group_name + '/' + dataset_name)
lat = h5d_read(data_id)
h5d_close, data_id

;- Read the longitude data
dataset_name = 'Longitude'
data_id = h5d_open(file_id, group_name + '/' + dataset_name)
lon = h5d_read(data_id)
h5d_close, data_id

;- Read the solar zenith angle data
dataset_name = 'SolarZenithAngle'
data_id = h5d_open(file_id, group_name + '/' + dataset_name)
zen = h5d_read(data_id)
h5d_close, data_id

;- Close the file
h5f_close, file_id

END