Interpolate State to Gaussian Grid

src/mains/CMakeLists.txt

@@ -80,6 +80,11 @@ ecbuild_add_executable( TARGET  soca_convertstate.x
                         LIBS    soca
                       )
 
+ecbuild_add_executable( TARGET  soca_converttostructuredgrid.x
+			SOURCES ConvertToStructuredGrid.cc
+                        LIBS    soca
+                      )
+
 ecbuild_add_executable( TARGET  soca_addincrement.x
                         SOURCES AddIncrement.cc
                         LIBS    soca

src/mains/ConvertToStructuredGrid.cc

@@ -0,0 +1,18 @@
+/*
+ * (C) Copyright 2017-2024 UCAR
+ *
+ * This software is licensed under the terms of the Apache Licence Version 2.0
+ * which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
+ */
+
+
+#include "oops/runs/ConvertToStructuredGrid.h"
+#include "oops/runs/Run.h"
+#include "soca/Traits.h"
+
+int main(int argc,  char ** argv) {
+  oops::Run run(argc, argv);
+  oops::ConvertToStructuredGrid<soca::Traits> converttostructuredgrid;
+  return run.execute(converttostructuredgrid);
+}
+

test/CMakeLists.txt

@@ -35,6 +35,7 @@ set( soca_test_input
   testinput/convertstate_changevar.yml
   testinput/convertstate_soca2cice.yml
   testinput/convertstate.yml
+  testinput/converttogauss.yml
   testinput/diffstates.yml
   testinput/dirac_diffusion.yml
   testinput/dirac_diffusion_lowres.yml
@@ -120,6 +121,7 @@ set( soca_test_ref
   testref/convertstate_changevar.test
   testref/convertstate_soca2cice.test
   testref/convertstate.test
+  testref/converttogauss.test
   testref/diffstates.test
   testref/dirac_diffusion.test
   testref/dirac_parametric_ocean_stddev.test
@@ -536,6 +538,11 @@ soca_add_test( NAME convertstate
               #  NOTRAPFPE
                TEST_DEPENDS test_soca_gridgen )
 
+# Convert to Gaussian grid
+soca_add_test( NAME converttogauss
+               EXE  soca_converttostructuredgrid.x
+               TEST_DEPENDS test_soca_gridgen )
+
 # Apply a nonlinear change of variable to an ensemble of states
 soca_add_test( NAME convertstate_changevar
                EXE  soca_convertstate.x

test/testinput/converttogauss.yml

@@ -0,0 +1,40 @@
+states to structured grid:
+- state geometry:
+    geom_grid_file: data_generated/gridgen/soca_gridspec.72x35x25.nc
+    mom6_input_nml: data_static/72x35x25/input.nml
+    fields metadata: data_static/fields_metadata.yml
+
+  state:
+    read_from_file: 1
+    basename: data_static/72x35x25/restarts/
+    ocn_filename: MOM.res.nc
+    ice_filename: cice.res.nc
+    sfc_filename: sfc.res.nc
+    date: &bkg_date 2018-04-15T00:00:00Z
+    state variables:
+    - sea_surface_height_above_geoid
+    - sea_water_potential_temperature
+    - sea_water_salinity
+    - sea_water_cell_thickness
+    - sea_ice_area_fraction
+    - sea_water_depth
+
+  structured grid interpolation:
+    grid type: regular gaussian
+    local interpolator type: atlas interpolator
+    interpolation method:
+      type: finite-element
+    number of latitude gridpoints: 12
+    variables to output:
+    - sea_surface_height_above_geoid
+    - sea_water_potential_temperature
+    - sea_water_salinity
+    - sea_ice_area_fraction
+    all model levels: true
+    bottom model level: false
+    datapath: data_output/
+    prefix: converttogauss
+test:
+  reference filename: testref/converttogauss.test
+  test output filename: testoutput/converttogauss.test
+  float relative tolerance: 1.0e-3

test/testref/converttogauss.test

@@ -0,0 +1,4 @@
+StructuredGridWriter::<SOCA>
+Grid Resolution: 12
+Variables: 4 variables: sea_surface_height_above_geoid, sea_water_potential_temperature, sea_water_salinity, sea_ice_area_fraction
+Output on Levels: All Model Levels