How can I read variables (lat lon and chl-a)in nc files with groups?

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Hi,
I download Aqua-MODIS nc file from Level-3 Binned/Aqua-MODIS/2019/064 (nasa.gov),the file is too large to upload.
I already used the command "chla_a=ncread("H:\chla\A2019352.L3b_DAY_CHL.nc",'/level-3_binned_data/chlor_a');" to read data, however, it is wrong-"Incorrect use of netcdf.getVar (line 137)33 is an unrecognized netCDF data type."
I want to know how can I read the chl-a data and it lat and lon?
Below is the information:
ncdisp("H:\chla\A2019352.L3b_DAY_CHL.nc")
Source:
H:\chla\A2019352.L3b_DAY_CHL.nc
Format:
netcdf4
Global Attributes:
product_name = 'A2019352.L3b_DAY_CHL.nc'
title = 'MODIS Level-3 Binned Data'
instrument = 'MODIS'
platform = 'Aqua'
temporal_range = 'day'
start_orbit_number = 93736
end_orbit_number = 93751
date_created = '2020-04-01T00:40:24.000Z'
processing_version = '2018.1'
history = 'l2bin par=A2019352.L3b_DAY_CHL.param'
time_coverage_start = '2019-12-18T00:20:01.000Z'
time_coverage_end = '2019-12-19T02:34:59.000Z'
northernmost_latitude = 90
southernmost_latitude = -90
easternmost_longitude = 180
westernmost_longitude = -180
geospatial_lat_max = 90
geospatial_lat_min = -90
geospatial_lon_max = 180
geospatial_lon_min = -180
geospatial_lat_units = 'degrees_north'
geospatial_lon_units = 'degrees_east'
geospatial_lon_resolution = 0.041667
geospatial_lat_resolution = 0.041667
spatialResolution = '4.6 km'
data_bins = 1468593
percent_data_bins = 6.1805
units = 'chlor_a:mg m^-3,chl_ocx:mg m^-3'
binning_scheme = 'Integerized Sinusoidal Grid'
project = 'Ocean Biology Processing Group (NASA/GSFC/OBPG)'
institution = 'NASA Goddard Space Flight Center, Ocean Ecology Laboratory, Ocean Biology Processing Group'
standard_name_vocabulary = 'CF Standard Name Table v36'
Conventions = 'CF-1.6 ACDD-1.3'
naming_authority = 'gov.nasa.gsfc.sci.oceandata'
id = 'A2019352.L3b_DAY_CHL.nc/L3/A2019352.L3b_DAY_CHL.nc'
license = 'https://science.nasa.gov/earth-science/earth-science-data/data-information-policy/'
creator_name = 'NASA/GSFC/OBPG'
publisher_name = 'NASA/GSFC/OBPG'
creator_email = 'data@oceancolor.gsfc.nasa.gov'
publisher_email = 'data@oceancolor.gsfc.nasa.gov'
creator_url = 'https://oceandata.sci.gsfc.nasa.gov'
publisher_url = 'https://oceandata.sci.gsfc.nasa.gov'
processing_level = 'L3 Binned'
cdm_data_type = 'point'
identifier_product_doi_authority = 'https://dx.doi.org'
identifier_product_doi = '10.5067/AQUA/MODIS/L3B/CHL/2018'
keywords_vocabulary = 'NASA Global Change Master Directory (GCMD) Science Keywords'
keywords = 'Earth Science > Oceans > Ocean Chemistry > Pigments > Chlorophyll; Earth Science > Oceans > Ocean Chemistry > Chlorophyllr'
Groups:
/level-3_binned_data/
Dimensions:
binListDim = 1468593 (UNLIMITED)
binDataDim = 1468593 (UNLIMITED)
binIndexDim = 4320 (UNLIMITED)
Variables:
BinList
Size: 1468593x1
Dimensions: binListDim
Datatype: UNSUPPORTED DATATYPE
chlor_a
Size: 1468593x1
Dimensions: binDataDim
Datatype: UNSUPPORTED DATATYPE
chl_ocx
Size: 1468593x1
Dimensions: binDataDim
Datatype: UNSUPPORTED DATATYPE
BinIndex
Size: 4320x1
Dimensions: binIndexDim
Datatype: UNSUPPORTED DATATYPE
/processing_control/
Attributes:
software_name = 'l2bin'
software_version = '6.2.0'
source = 'A2019352000000.L2_LAC_OC.nc,A2019352000500.L2_LAC_OC.nc,A2019352001000.L2_LAC_OC.nc,A2019352001500.L2_LAC_OC.nc,A2019352002000.L2_LAC_OC.nc,A2019352002500.L2_LAC_OC.nc,A2019352003000.L2_LAC_OC.nc,A2019352012000.L2_LAC_OC.nc,A2019352012500.L2_LAC_OC.nc,A2019352013000.L2_LAC_OC.nc,A2019352013500.L2_LAC_OC.nc,A2019352014000.L2_LAC_OC.nc,A2019352014500.L2_LAC_OC.nc,A2019352015000.L2_LAC_OC.nc,A2019352015500.L2_LAC_OC.nc,A2019352020000.L2_LAC_OC.nc,A2019352020500.L2_LAC_OC.nc,A2019352021000.L2_LAC_OC.nc,A2019352025500.L2_LAC_OC.nc,A2019352030000.L2_LAC_OC.nc,A2019352030500.L2_LAC_OC.nc,A2019352031000.L2_LAC_OC.nc,A2019352031500.L2_LAC_OC.nc,A2019352032000.L2_LAC_OC.nc,A2019352032500.L2_LAC_OC.nc,A2019352033000.L2_LAC_OC.nc,A2019352033500.L2_LAC_OC.nc,A2019352034000.L2_LAC_OC.nc,A2019352034500.L2_LAC_OC.nc,A2019352035000.L2_LAC_OC.nc,A2019352043500.L2_LAC_OC.nc,A2019352044000.L2_LAC_OC.nc,A2019352044500.L2_LAC_OC.nc,A2019352045000.L2_LAC_OC.nc,A2019352045500.L2_LAC_OC.nc,A2019352050000.L2_LAC_OC.nc,A2019352050500.L2_LAC_OC.nc,A2019352051000.L2_LAC_OC.nc,A2019352051500.L2_LAC_OC.nc,A2019352052000.L2_LAC_OC.nc,A2019352052500.L2_LAC_OC.nc,A2019352053000.L2_LAC_OC.nc,A2019352061500.L2_LAC_OC.nc,A2019352062000.L2_LAC_OC.nc,A2019352062500.L2_LAC_OC.nc,A2019352063000.L2_LAC_OC.nc,A2019352063500.L2_LAC_OC.nc,A2019352064000.L2_LAC_OC.nc,A2019352064500.L2_LAC_OC.nc,A2019352065000.L2_LAC_OC.nc,A2019352065500.L2_LAC_OC.nc,A2019352070000.L2_LAC_OC.nc,A2019352070500.L2_LAC_OC.nc,A2019352075500.L2_LAC_OC.nc,A2019352080000.L2_LAC_OC.nc,A2019352080500.L2_LAC_OC.nc,A2019352081000.L2_LAC_OC.nc,A2019352081500.L2_LAC_OC.nc,A2019352082000.L2_LAC_OC.nc,A2019352082500.L2_LAC_OC.nc,A2019352083000.L2_LAC_OC.nc,A2019352083500.L2_LAC_OC.nc,A2019352084000.L2_LAC_OC.nc,A2019352084500.L2_LAC_OC.nc,A2019352093000.L2_LAC_OC.nc,A2019352093500.L2_LAC_OC.nc,A2019352094000.L2_LAC_OC.nc,A2019352094500.L2_LAC_OC.nc,A2019352095000.L2_LAC_OC.nc,A2019352095500.L2_LAC_OC.nc,A2019352100000.L2_LAC_OC.nc,A2019352100500.L2_LAC_OC.nc,A2019352101000.L2_LAC_OC.nc,A2019352101500.L2_LAC_OC.nc,A2019352102000.L2_LAC_OC.nc,A2019352102500.L2_LAC_OC.nc,A2019352111000.L2_LAC_OC.nc,A2019352111500.L2_LAC_OC.nc,A2019352112000.L2_LAC_OC.nc,A2019352112500.L2_LAC_OC.nc,A2019352113000.L2_LAC_OC.nc,A2019352113500.L2_LAC_OC.nc,A2019352114000.L2_LAC_OC.nc,A2019352114500.L2_LAC_OC.nc,A2019352115000.L2_LAC_OC.nc,A2019352115500.L2_LAC_OC.nc,A2019352120000.L2_LAC_OC.nc,A2019352120500.L2_LAC_OC.nc,A2019352125000.L2_LAC_OC.nc,A2019352125500.L2_LAC_OC.nc,A2019352130000.L2_LAC_OC.nc,A2019352130500.L2_LAC_OC.nc,A2019352131000.L2_LAC_OC.nc,A2019352131500.L2_LAC_OC.nc,A2019352132000.L2_LAC_OC.nc,A2019352132500.L2_LAC_OC.nc,A2019352133000.L2_LAC_OC.nc,A2019352133500.L2_LAC_OC.nc,A2019352134000.L2_LAC_OC.nc,A2019352143000.L2_LAC_OC.nc,A2019352143500.L2_LAC_OC.nc,A2019352144000.L2_LAC_OC.nc,A2019352144500.L2_LAC_OC.nc,A2019352145000.L2_LAC_OC.nc,A2019352145500.L2_LAC_OC.nc,A2019352150000.L2_LAC_OC.nc,A2019352150500.L2_LAC_OC.nc,A2019352151000.L2_LAC_OC.nc,A2019352151500.L2_LAC_OC.nc,A2019352152000.L2_LAC_OC.nc,A2019352161000.L2_LAC_OC.nc,A2019352161500.L2_LAC_OC.nc,A2019352162000.L2_LAC_OC.nc,A2019352162500.L2_LAC_OC.nc,A2019352163000.L2_LAC_OC.nc,A2019352163500.L2_LAC_OC.nc,A2019352164000.L2_LAC_OC.nc,A2019352164500.L2_LAC_OC.nc,A2019352165000.L2_LAC_OC.nc,A2019352165500.L2_LAC_OC.nc,A2019352170000.L2_LAC_OC.nc,A2019352174500.L2_LAC_OC.nc,A2019352175000.L2_LAC_OC.nc,A2019352175500.L2_LAC_OC.nc,A2019352180000.L2_LAC_OC.nc,A2019352180500.L2_LAC_OC.nc,A2019352181000.L2_LAC_OC.nc,A2019352181500.L2_LAC_OC.nc,A2019352182000.L2_LAC_OC.nc,A2019352182500.L2_LAC_OC.nc,A2019352183000.L2_LAC_OC.nc,A2019352183500.L2_LAC_OC.nc,A2019352184000.L2_LAC_OC.nc,A2019352192500.L2_LAC_OC.nc,A2019352193000.L2_LAC_OC.nc,A2019352193500.L2_LAC_OC.nc,A2019352194000.L2_LAC_OC.nc,A2019352194500.L2_LAC_OC.nc,A2019352195000.L2_LAC_OC.nc,A2019352195500.L2_LAC_OC.nc,A2019352200000.L2_LAC_OC.nc,A2019352200500.L2_LAC_OC.nc,A2019352201000.L2_LAC_OC.nc,A2019352201500.L2_LAC_OC.nc,A2019352202000.L2_LAC_OC.nc,A2019352210500.L2_LAC_OC.nc,A2019352211000.L2_LAC_OC.nc,A2019352211500.L2_LAC_OC.nc,A2019352212000.L2_LAC_OC.nc,A2019352212500.L2_LAC_OC.nc,A2019352213000.L2_LAC_OC.nc,A2019352213500.L2_LAC_OC.nc,A2019352214000.L2_LAC_OC.nc,A2019352214500.L2_LAC_OC.nc,A2019352215000.L2_LAC_OC.nc,A2019352215500.L2_LAC_OC.nc,A2019352224500.L2_LAC_OC.nc,A2019352225000.L2_LAC_OC.nc,A2019352225500.L2_LAC_OC.nc,A2019352230000.L2_LAC_OC.nc,A2019352230500.L2_LAC_OC.nc,A2019352231000.L2_LAC_OC.nc,A2019352231500.L2_LAC_OC.nc,A2019352232000.L2_LAC_OC.nc,A2019352232500.L2_LAC_OC.nc,A2019352233000.L2_LAC_OC.nc,A2019352233500.L2_LAC_OC.nc,A2019353002000.L2_LAC_OC.nc,A2019353002500.L2_LAC_OC.nc,A2019353003000.L2_LAC_OC.nc,A2019353003500.L2_LAC_OC.nc,A2019353004000.L2_LAC_OC.nc,A2019353004500.L2_LAC_OC.nc,A2019353005000.L2_LAC_OC.nc,A2019353005500.L2_LAC_OC.nc,A2019353010000.L2_LAC_OC.nc,A2019353010500.L2_LAC_OC.nc,A2019353011000.L2_LAC_OC.nc,A2019353011500.L2_LAC_OC.nc,A2019353020000.L2_LAC_OC.nc,A2019353020500.L2_LAC_OC.nc,A2019353021000.L2_LAC_OC.nc,A2019353021500.L2_LAC_OC.nc,A2019353022000.L2_LAC_OC.nc,A2019353022500.L2_LAC_OC.nc,A2019353023000.L2_LAC_OC.nc,A2019353023500.L2_LAC_OC.nc,A2019353024000.L2_LAC_OC.nc,A2019353024500.L2_LAC_OC.nc,A2019353025000.L2_LAC_OC.nc,A2019353025500.L2_LAC_OC.nc'
l2_flag_names = 'ATMFAIL,LAND,HILT,HISATZEN,STRAYLIGHT,CLDICE,COCCOLITH,LOWLW,CHLWARN,CHLFAIL,NAVWARN,MAXAERITER,ATMWARN,HISOLZEN,NAVFAIL,FILTER,HIGLINT'
Groups:
/processing_control/input_parameters/
Attributes:
infile = '/data7/sdpsoper/vdc/vpu20/workbuf/l2inlist.dat'
ofile = 'A2019352.L3b_DAY_CHL.nc'
fileuse = 'A2019352.L3b_DAY_CHL.contrib'
sday = '2019352'
eday = '2019352'
latnorth = '90.000000'
latsouth = '-90.000000'
loneast = '0.000000'
lonwest = '0.000000'
resolve = '4'
rowgroup = '270'
flaguse = 'ATMFAIL,LAND,HILT,HISATZEN,STRAYLIGHT,CLDICE,COCCOLITH,LOWLW,CHLWARN,CHLFAIL,NAVWARN,MAXAERITER,ATMWARN,HISOLZEN,NAVFAIL,FILTER,HIGLINT'
l3bprod = 'chlor_a,chl_ocx'
prodtype = 'O'
pversion = '2018.1'
suite = 'CHL'
night = '0'
verbose = '0'
minobs = '0'
deflate = '4'
qual_prod = ''
composite_prod = ''
composite_scheme = ''
qual_max = '2'
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
chla_a=ncread("H:\chla\A2019352.L3b_DAY_CHL.nc",'/level-3_binned_data/chlor_a');
Incorrect use of netcdf.getVar (line 137)
33 is an unrecognized netCDF data type.
Error in internal.matlab.imagesci.nc/read (line 607)
data = netcdf.getVar(gid, varid);
Error ncread (line 66)
vardata = ncObj.read(varName, varargin{:});
Thank you very much! I need your help.

Accepted Answer

MJFcoNaN
MJFcoNaN on 4 Jul 2022
Edited: MJFcoNaN on 4 Jul 2022
Hello,
If possible, I will suggest you choose the "level 3 mapped data" which is much more convenient to deal with in matlab, because of its traditional lon-lat grid.
Or you need to use h5read instead of ncread:
chla_a=h5read("H:\chla\A2019352.L3b_DAY_CHL.nc","/level-3_binned_data/chlor_a");

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