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Re: HDF 4 > ncml?

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  • Subject: Re: HDF 4 > ncml?
  • Date: Mon, 04 Aug 2008 07:12:18 -0600
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