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Thanks Peter. The HDF4 reading is new, so if anyone sees something that looks funny compared to the original file, please let me know. Peter Hollemans wrote:
Hi John, I didn't know that the latest Java netCDF could read HDF-4! I did a dump of a CoastWatch file for Ted:phollema@bean<Downloads> java -cp toolsUI-4.0.jar ucar.nc2.NCdump $HOME/Data/2006_249_2137_n18_wn.hdf -ncml log4j:WARN No appenders could be found for logger (ucar.nc2.NetcdfFile). log4j:WARN Please initialize the log4j system properly. <?xml version='1.0' encoding='UTF-8'?> <netcdf xmlns='http://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2' location='file:/Users/phollema/Data/2006_249_2137_n18_wn.hdf' > <dimension name='rows' length='1024' /> <dimension name='cols' length='1024' /> <attribute name='satellite' value='noaa-18' /> <attribute name='sensor' value='avhrr' /> <attribute name='origin' value='USDOC/NOAA/NESDIS CoastWatch' /> <attribute name='cwhdf_version' value='3.4' /> <attribute name='pass_type' value='day' /> <attribute name='pass_date' value='13397 ' type='int' /> <attribute name='start_time' value='77824.0 ' type='double' /> <attribute name='projection_type' value='mapped' /> <attribute name='projection' value='Mercator' /> <attribute name='gctp_sys' value='5 ' type='int' /> <attribute name='gctp_zone' value='0 ' type='int' /> <attribute name='gctp_parm' value='0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 ' type='double' /> <attribute name='gctp_datum' value='12 ' type='int' /> <attribute name='et_affine' value='0.0 -1470.0 1470.0 0.0 -1.5028629694237337E7 6343200.918551117 ' type='double' /> <attribute name='rows' value='1024 ' type='int' /> <attribute name='cols' value='1024 ' type='int' /> <attribute name='polygon_latitude' value='49.59106659023744 49.59106659023744 49.59106659023744 49.59106659023744 49.59106659023744 47.3457234175452 44.99999999998704 42.55345611162261 40.00635240249667 40.00635240249667 40.00635240249667 40.00635240249667 40.00635240249667 42.55345611162261 44.99999999998704 47.3457234175452 49.59106659023744 ' type='double' /> <attribute name='polygon_longitude' value='-135.0044775370589 -131.62723876852945 -128.25 -124.87276123147056 -121.49552246294114 -121.49552246294114 -121.49552246294114 -121.49552246294114 -121.49552246294114 -124.87276123147056 -128.25 -131.62723876852945 -135.0044775370589 -135.0044775370589 -135.0044775370589 -135.0044775370589 -135.0044775370589 ' type='double' /> <attribute name='history' value='[cwf 3.1.10-pre] cwimport product.tshdf product.hdf' /> <attribute name='History' value='Direct read of HDF4 file through CDM library' /> <attribute name='HDF4_Version' value='4.1.5 (NCSA HDF Version 4.1 Release 5, November 5, 2001)' /> <variable name='avhrr_ch1' type='short' shape='rows cols' > <attribute name='long_name' value='avhrr_ch1' /> <attribute name='units' value='percent' /> <attribute name='coordsys' value='Mercator' /> <attribute name='_FillValue' value='-32768 ' type='short' /> <attribute name='missing_value' value='-32768 ' type='short' /> <attribute name='scale_factor' value='0.01 ' type='double' /> <attribute name='scale_factor_err' value='0.0 ' type='double' /> <attribute name='add_offset' value='0.0 ' type='double' /> <attribute name='add_offset_err' value='0.0 ' type='double' /> <attribute name='calibrated_nt' value='0 ' type='int' /> <attribute name='fraction_digits' value='2 ' type='int' /> </variable> <variable name='avhrr_ch2' type='short' shape='rows cols' > <attribute name='long_name' value='avhrr_ch2' /> <attribute name='units' value='percent' /> <attribute name='coordsys' value='Mercator' /> <attribute name='_FillValue' value='-32768 ' type='short' /> <attribute name='missing_value' value='-32768 ' type='short' /> <attribute name='scale_factor' value='0.01 ' type='double' /> <attribute name='scale_factor_err' value='0.0 ' type='double' /> <attribute name='add_offset' value='0.0 ' type='double' /> <attribute name='add_offset_err' value='0.0 ' type='double' /> <attribute name='calibrated_nt' value='0 ' type='int' /> <attribute name='fraction_digits' value='2 ' type='int' /> </variable> <variable name='avhrr_ch3' type='short' shape='rows cols' > <attribute name='long_name' value='avhrr_ch3' /> <attribute name='units' value='celsius' /> <attribute name='coordsys' value='Mercator' /> <attribute name='_FillValue' value='-32768 ' type='short' /> <attribute name='missing_value' value='-32768 ' type='short' /> <attribute name='scale_factor' value='0.01 ' type='double' /> <attribute name='scale_factor_err' value='0.0 ' type='double' /> <attribute name='add_offset' value='0.0 ' type='double' /> <attribute name='add_offset_err' value='0.0 ' type='double' /> <attribute name='calibrated_nt' value='0 ' type='int' /> <attribute name='fraction_digits' value='2 ' type='int' /> </variable> <variable name='avhrr_ch4' type='short' shape='rows cols' > <attribute name='long_name' value='avhrr_ch4' /> <attribute name='units' value='celsius' /> <attribute name='coordsys' value='Mercator' /> <attribute name='_FillValue' value='-32768 ' type='short' /> <attribute name='missing_value' value='-32768 ' type='short' /> <attribute name='scale_factor' value='0.01 ' type='double' /> <attribute name='scale_factor_err' value='0.0 ' type='double' /> <attribute name='add_offset' value='0.0 ' type='double' /> <attribute name='add_offset_err' value='0.0 ' type='double' /> <attribute name='calibrated_nt' value='0 ' type='int' /> <attribute name='fraction_digits' value='2 ' type='int' /> <attribute name='nav_affine' value='1.0 0.0 0.0 1.0 0.0 0.0 ' type='double' /> </variable> <variable name='avhrr_ch5' type='short' shape='rows cols' > <attribute name='long_name' value='avhrr_ch5' /> <attribute name='units' value='celsius' /> <attribute name='coordsys' value='Mercator' /> <attribute name='_FillValue' value='-32768 ' type='short' /> <attribute name='missing_value' value='-32768 ' type='short' /> <attribute name='scale_factor' value='0.01 ' type='double' /> <attribute name='scale_factor_err' value='0.0 ' type='double' /> <attribute name='add_offset' value='0.0 ' type='double' /> <attribute name='add_offset_err' value='0.0 ' type='double' /> <attribute name='calibrated_nt' value='0 ' type='int' /> <attribute name='fraction_digits' value='2 ' type='int' /> </variable> <variable name='cloud' type='byte' shape='rows cols' > <attribute name='_unsigned' value='true' /> <attribute name='long_name' value='cloud' /> <attribute name='coordsys' value='Mercator' /> <attribute name='_FillValue' value='0 ' type='byte' /> <attribute name='missing_value' value='0 ' type='byte' /> <attribute name='scale_factor' value='1.0 ' type='double' /> <attribute name='scale_factor_err' value='0.0 ' type='double' /> <attribute name='add_offset' value='0.0 ' type='double' /> <attribute name='add_offset_err' value='0.0 ' type='double' /> <attribute name='calibrated_nt' value='0 ' type='int' /> <attribute name='fraction_digits' value='1 ' type='int' /> </variable> <variable name='graphics' type='byte' shape='rows cols' > <attribute name='_unsigned' value='true' /> <attribute name='long_name' value='graphics' /> <attribute name='coordsys' value='Mercator' /> <attribute name='_FillValue' value='0 ' type='byte' /> <attribute name='missing_value' value='0 ' type='byte' /> <attribute name='scale_factor' value='1.0 ' type='double' /> <attribute name='scale_factor_err' value='0.0 ' type='double' /> <attribute name='add_offset' value='0.0 ' type='double' /> <attribute name='add_offset_err' value='0.0 ' type='double' /> <attribute name='calibrated_nt' value='0 ' type='int' /> <attribute name='fraction_digits' value='1 ' type='int' /> </variable> <variable name='rel_azimuth' type='short' shape='rows cols' > <attribute name='long_name' value='rel_azimuth' /> <attribute name='units' value='degrees' /> <attribute name='coordsys' value='Mercator' /> <attribute name='_FillValue' value='-32768 ' type='short' /> <attribute name='missing_value' value='-32768 ' type='short' /> <attribute name='scale_factor' value='0.01 ' type='double' /> <attribute name='scale_factor_err' value='0.0 ' type='double' /> <attribute name='add_offset' value='0.0 ' type='double' /> <attribute name='add_offset_err' value='0.0 ' type='double' /> <attribute name='calibrated_nt' value='0 ' type='int' /> <attribute name='fraction_digits' value='2 ' type='int' /> </variable> <variable name='sat_zenith' type='short' shape='rows cols' > <attribute name='long_name' value='sat_zenith' /> <attribute name='units' value='degrees' /> <attribute name='coordsys' value='Mercator' /> <attribute name='_FillValue' value='-32768 ' type='short' /> <attribute name='missing_value' value='-32768 ' type='short' /> <attribute name='scale_factor' value='0.01 ' type='double' /> <attribute name='scale_factor_err' value='0.0 ' type='double' /> <attribute name='add_offset' value='0.0 ' type='double' /> <attribute name='add_offset_err' value='0.0 ' type='double' /> <attribute name='calibrated_nt' value='0 ' type='int' /> <attribute name='fraction_digits' value='2 ' type='int' /> </variable> <variable name='sst' type='short' shape='rows cols' > <attribute name='long_name' value='sst' /> <attribute name='units' value='celsius' /> <attribute name='coordsys' value='Mercator' /> <attribute name='_FillValue' value='-32768 ' type='short' /> <attribute name='missing_value' value='-32768 ' type='short' /> <attribute name='scale_factor' value='0.01 ' type='double' /> <attribute name='scale_factor_err' value='0.0 ' type='double' /> <attribute name='add_offset' value='0.0 ' type='double' /> <attribute name='add_offset_err' value='0.0 ' type='double' /> <attribute name='calibrated_nt' value='0 ' type='int' /> <attribute name='fraction_digits' value='2 ' type='int' /> </variable> <variable name='sun_zenith' type='short' shape='rows cols' > <attribute name='long_name' value='sun_zenith' /> <attribute name='units' value='degrees' /> <attribute name='coordsys' value='Mercator' /> <attribute name='_FillValue' value='-32768 ' type='short' /> <attribute name='missing_value' value='-32768 ' type='short' /> <attribute name='scale_factor' value='0.01 ' type='double' /> <attribute name='scale_factor_err' value='0.0 ' type='double' /> <attribute name='add_offset' value='0.0 ' type='double' /> <attribute name='add_offset_err' value='0.0 ' type='double' /> <attribute name='calibrated_nt' value='0 ' type='int' /> <attribute name='fraction_digits' value='2 ' type='int' /> </variable> </netcdf> phollema@bean<Downloads>Best regards, Peter -- Peter Hollemans, Terrenus Earth Sciences Consultant for the NOAA/NESDIS CoastWatch Program Phone: (250) 478-1006 Email: address@hidden On 3-Aug-08, at 4:28 PM, John Caron wrote:Hi Ted: Look at "NcML as output" section in http://www.unidata.ucar.edu/software/netcdf/ncml/. Be sure to use the latest version of Netcdf-Java version 4.0 to read HDF-4 files. However you cant use ncdump -x, because the netCDF C library doesnt read HDF-4 files. Im guessing Peter and Mike are talking about a version of ncdump supplied by hdfgroup.org? Ted Habermann wrote:Hello All, The NOAA CoastWatch Program provides data in HDF4 files which include a bunch of high-quality metadata (attributes) that I would like to extract. Seems like a good idea to extract them in XML, maybe even a better idea to extract them in NCML. I figured you guys would know if a tool existed to do this... Ted