feat: add EGM2008 interpolation programs for ICESat+OIB (#36)

fix: read cases in ATM level-2 data where a line is empty

doc/source/api_reference/geoid/interp_EGM2008_ICESat_GLA12.rst

@@ -0,0 +1,19 @@
+==============================
+interp_EGM2008_ICESat_GLA12.py
+==============================
+
+- Reads EGM2008 geoid height spatial grids from unformatted binary files provided by the National Geospatial-Intelligence Agency and interpolates to ICESat/GLAS L2 GLA12 Antarctic and Greenland Ice Sheet elevation data
+
+`Source code`__
+
+.. __: https://github.com/tsutterley/Grounding-Zones/blob/main/geoid/interp_EGM2008_ICESat_GLA12.py
+
+Calling Sequence
+################
+
+.. argparse::
+    :filename: interp_EGM2008_ICESat_GLA12.py
+    :func: arguments
+    :prog: interp_EGM2008_ICESat_GLA12.py
+    :nodescription:
+    :nodefault:

doc/source/api_reference/geoid/interp_EGM2008_icebridge_data.rst

@@ -0,0 +1,19 @@
+================================
+interp_EGM2008_icebridge_data.py
+================================
+
+- Reads EGM2008 geoid height spatial grids from unformatted binary files provided by the National Geospatial-Intelligence Agency and interpolates to Operation IceBridge elevation data
+
+`Source code`__
+
+.. __: https://github.com/tsutterley/Grounding-Zones/blob/main/geoid/interp_EGM2008_icebridge_data.py
+
+Calling Sequence
+################
+
+.. argparse::
+    :filename: interp_EGM2008_icebridge_data.py
+    :func: arguments
+    :prog: interp_EGM2008_icebridge_data.py
+    :nodescription:
+    :nodefault:

doc/source/index.rst

@@ -88,6 +88,8 @@ Python Tools for Estimating Ice Sheet Grounding Zone Locations with data from NA
     api_reference/geoid/compute_geoid_ICESat2_ATL10.rst
     api_reference/geoid/compute_geoid_ICESat2_ATL11.rst
     api_reference/geoid/compute_geoid_ICESat2_ATL12.rst
+    api_reference/geoid/interp_EGM2008_icebridge_data.rst
+    api_reference/geoid/interp_EGM2008_ICESat_GLA12.rst
 
 .. toctree::
     :maxdepth: 1

geoid/compute_geoid_ICESat_GLA12.py

@@ -386,7 +386,7 @@ def HDF5_GLA12_geoid_write(IS_gla12_geoid, IS_gla12_attrs,
 # PURPOSE: create argument parser
 def arguments():
     parser = argparse.ArgumentParser(
-        description="""Calculates geoid undunations for correcting ICESat/GLAS
+        description="""Calculates geoid undulations for correcting ICESat/GLAS
             L2 GLA12 Antarctic and Greenland Ice Sheet elevation data
             """,
         fromfile_prefix_chars="@"

geoid/compute_geoid_icebridge_data.py

@@ -160,10 +160,8 @@ def compute_geoid_icebridge_data(model_file, arg, LMAX=None, LOVE=None,
     attrib['geoid_free2mean'] = {}
     attrib['geoid_free2mean']['units'] = 'm'
     attrib['geoid_free2mean']['long_name'] = 'Geoid_Free-to-Mean_conversion'
-    args = (Ylms['modelname'],Ylms['max_degree'])
-    attrib['geoid_free2mean']['description'] = ('Additive value to convert '
-        'geoid heights from the tide-free system to the mean-tide system')
-    attrib['geoid_free2mean']['tide_system'] = Ylms['tide_system']
+    attrib['geoid_free2mean']['description'] = ('Additive_value_to_convert_'
+        'geoid_heights_from_the_tide-free_system_to_the_mean-tide_system')
     attrib['geoid_free2mean']['earth_gravity_constant'] = GM
     attrib['geoid_free2mean']['radius'] = R
     attrib['geoid_free2mean']['coordinates'] = 'lat lon'
@@ -203,7 +201,7 @@ def compute_geoid_icebridge_data(model_file, arg, LMAX=None, LOVE=None,
         dinput, file_lines, HEM = gz.io.icebridge.read_LVIS_HDF5_file(
             input_file, input_subsetter)
 
-    # output tidal HDF5 file
+    # output geoid HDF5 file
     # form: rg_NASA_model_GEOID_WGS84_fl1yyyymmddjjjjj.H5
     # where rg is the hemisphere flag (GR or AN) for the region
     # model is the geoid model name flag
@@ -243,8 +241,8 @@ def compute_geoid_icebridge_data(model_file, arg, LMAX=None, LOVE=None,
             data=dinput[key][:], dtype=dinput[key].dtype,
             compression='gzip')
         # add HDF5 variable attributes
-        for att_name,att_val in attributes:
-            h5.attrs[att_name] = att_val
+        for att_name,att_val in attributes.items():
+            h5[key].attrs[att_name] = att_val
         # attach dimensions
         if key not in ('time',):
             for i,dim in enumerate(['time']):
@@ -254,8 +252,7 @@ def compute_geoid_icebridge_data(model_file, arg, LMAX=None, LOVE=None,
     # HDF5 file attributes
     fid.attrs['featureType'] = 'trajectory'
     fid.attrs['title'] = 'Geoid_height_for_elevation_measurements'
-    fid.attrs['summary'] = ('Geoid_undulation_computed_at_elevation_'
-        'measurements_using_a_tidal_model_driver.')
+    fid.attrs['summary'] = 'Geoid_undulation_computed_at_elevation_measurements'
     fid.attrs['project'] = 'NASA_Operation_IceBridge'
     fid.attrs['processing_level'] = '4'
     fid.attrs['date_created'] = time.strftime('%Y-%m-%d',time.localtime())