Feature 1574 rotlatlon

met/docs/Users_Guide/README.rst

@@ -452,18 +452,7 @@ using the following entries:
 
   * to_grid = "path"; To regrid both to a grid defined by a file.
 
-  * to_grid = "spec"; To define a grid specified as follows:
-
-    * lambert Nx Ny lat_ll lon_ll lon_orient D_km R_km standard_parallel_1
-      [standard_parallel_2] N|S
-
-    * stereo Nx Ny lat_ll lon_ll lon_orient D_km R_km lat_scale N|S
-
-    * latlon Nx Ny lat_ll lon_ll delta_lat delta_lon
-
-    * mercator Nx Ny lat_ll lon_ll lat_ur lon_ur
-
-    * gaussian lon_zero Nx Ny
+  * to_grid = "spec"; To define a grid specification string, as described in :ref:`appendixB`.
 
 * The "vld_thresh" entry specifies a proportion between 0 and 1 to define
   the required ratio of valid data points. When regridding, compute
@@ -4004,25 +3993,7 @@ WWMCARegridConfig_default
 
 **to_grid**
 
-Specify the grid to which the data should be interpolated in one of the
-following ways:
-
-* Name ("GNNN" where NNN indicates the three digit NCEP grid number)
-
-* lambert Nx Ny lat_ll lon_ll lon_orient D_km R_km standard_parallel_1
-  [standard_parallel_2] N|S
-
-* stereo Nx Ny lat_ll lon_ll lon_orient D_km R_km lat_scale N|S
-
-* latlon Nx Ny lat_ll lon_ll delta_lat delta_lon
-
-* mercator Nx Ny lat_ll lon_ll lat_ur lon_ur
-
-* gaussian lon_zero Nx Ny
-
-.. code-block:: none
-
-  to_grid = "lambert 614 428 12.190 -133.459 -95.0 12.19058 6367.47 25.0 N";
+Please see the description of the "to_grid" entry in the "regrid" dictionary above.
 
 **NetCDF output information**  
 

met/docs/Users_Guide/appendixB.rst

@@ -22,10 +22,69 @@ The following map projections are currently supported in MET:
 
 * Gaussian Projection
 
+Grid Specification Strings
+__________________________
+
+Several configuration file and command line options support the definition of grids as a grid specification string. A description of the that string for each of the supported grid types is provided below.
+
+To specify a Lambert Grid, the syntax is
+
+.. code-block:: none
+
+  lambert Nx Ny lat_ll lon_ll lon_orient D_km R_km standard_lat_1 [ standard_lat_2 ] N|S
+
+Here, **Nx** and **Ny** are the number of points in, respectively, the **x** and **y** grid directions. These two numbers give the overall size of the grid. **lat_ll** and **lon_ll** are the latitude and longitude, in degrees, of the lower left point of the grid. North latitude and east longitude are considered positive. **lon_orient** is the orientation longitude of the grid. It’s the meridian of longitude that’s parallel to one of the vertical grid directions. **D_km** and **R_km** are the grid resolution and the radius of the Earth, both in kilometers. **standard_lat_1** and **standard_lat_2** are the standard parallels of the Lambert projection. If the two latitudes are the same, then only one needs to be given. **N|S** means to write either **N** or **S** depending on whether the Lambert projection is from the north pole or the south pole.
+
+As an example of specifying a Lambert grid, suppose you have a northern hemisphere Lambert grid with 614 points in the x direction and 428 points in the y direction. The lower left corner of the grid is at latitude :math:`12.190^\circ` north and longitude :math:`133.459^\circ` west. The orientation longitude is :math:`95^\circ` west. The grid spacing is :math:`12.19058^\circ` km. The radius of the Earth is the default value used in many grib files: 6367.47 km. Both standard parallels are at :math:`25^\circ` north. To specify this grid in the config file, you would write
+
+.. code-block:: none
+
+  To grid = "lambert 614 428 12.190 -133.459 -95.0 12.19058 6367.47 25.0 N";
+
+For a Polar Stereographic grid, the syntax is
+
+.. code-block:: none
+
+  stereo Nx Ny lat_ll lon_ll lon_orient D_km R_km lat_scale N|S
+
+Here, **Nx, Ny, lat_ll, lon_ll, lon_orient, D_km** and **R_km** have the same meaning as in the Lambert case. **lat_scale** is the latitude where the grid scale **D_km** is true, while **N|S** means to write either **N** or **S** depending on whether the stereographic projection is from the north pole or the south pole.
+
+For Plate Carrée (i.e. Lat/Lon) grids, the syntax is
+
+.. code-block:: none
+
+  latlon Nx Ny lat_ll lon_ll delta_lat delta_lon
+
+The parameters **Nx, Ny, lat_ll** and **lon_ll** are as before. **delta_lat** and **delta_lon** are the latitude and longitude increments of the grid—i.e., the change in latitude or longitude between one grid point and an adjacent grid point.
+
+For a Rotated Plate Carrée (i.e. Rotated Lat/Lon) grids, the syntax is
+
+.. code-block:: none
+
+  rotlatlon Nx Ny lat_ll lon_ll delta_lat delta_lon true_lat_sp true_lon_sp aux_rotation
+
+The parameters **Nx, Ny, lat_ll, lon_ll, delta_lat,** and **delta_lon** are as before. **true_lat_sp** and **true_lon_sp** are the latitude and longitude for the south pole. **aux_rotation** is the auxilary rotation in degrees.
+
+For a Mercator grid, the syntax is
+
+.. code-block:: none
+
+  mercator Nx Ny lat_ll lon_ll lat_ur lon_ur
+
+The parameters **Nx, Ny, lat_ll** and **lon_ll** are again as before, while **lat_ur** and **lon_ur** are the latitude and longitude of the upper right corner of the grid.
+
+For a Gaussian grid, the syntax is
+
+.. code-block:: none
+
+  gaussian lon_zero Nx Ny
+
+The parameters **Nx** and **Ny** are as before, while **lon_zero** defines the first longitude.
+
 Grids
 _____
 
-All of NCEP's pre-defined grids that reside on one of the projections listed above are implemented in MET. The user may specify one of these NCEP grids in the configuration files as "GNNN" where NNN is the 3-digit NCEP grid number. Defining a new masking grid in MET would involve modifying the vx_data_grids library and recompiling.
+The majority of NCEP's pre-defined grids that reside on one of the projections listed above are implemented in MET. The user may specify one of these NCEP grids in the configuration files as "GNNN" where NNN is the 3-digit NCEP grid number. Defining a new masking grid in MET would involve modifying the vx_data_grids library and recompiling.
 
 Please see `NCEP's website for a description and plot of these predefined grids <http://www.nco.ncep.noaa.gov/pmb/docs/on388/tableb.html>`_.
 

met/docs/Users_Guide/appendixE.rst

@@ -43,45 +43,7 @@ Now let’s talk about the details of the config file. The config file has the s
 
   To grid = "G218";
 
-and that will work. Failing that, you must give the parameters that specify the grid and it’s projection. Four projections are supported: Lambert Conformal, Polar Stereographic, Plate Carrée, and Mercator.
-
-To specify a Lambert Grid, the syntax is
-
-.. code-block:: none
-
-  lambert Nx Ny lat_ll lon_ll lon_orient D_km R_km standard_lat_1 [ standard_lat_2 ] N|S
-
-Here, **Nx** and **Ny** are the number of points in, respectively, the **x** and **y** grid directions. These two numbers give the overall size of the grid. **lat_ll** and **lon_ll** are the latitude and longitude, in degrees, of the lower left point of the grid. North latitude and east longitude are considered positive. **lon_orient** is the orientation longitude of the grid. It’s the meridian of longitude that’s parallel to one of the vertical grid directions. **D_km** and **R_km** are the grid resolution and the radius of the Earth, both in kilometers. **standard_lat_1** and **standard_lat_2** are the standard parallels of the Lambert projection. If the two latitudes are the same, then only one needs to be given. **N|S** means to write either **N** or **S** depending on whether the Lambert projection is from the north pole or the south pole.
-
-As an example of specifying a Lambert grid, suppose you have a northern hemisphere Lambert grid with 614 points in the x direction and 428 points in the y direction. The lower left corner of the grid is at latitude :math:`12.190^\circ` north and longitude :math:`133.459^\circ` west. The orientation longitude is :math:`95^\circ` west. The grid spacing is :math:`12.19058^\circ` km. The radius of the Earth is the default value used in many grib files: 6367.47 km. Both standard parallels are at :math:`25^\circ` north. To specify this grid in the config file, you would write
-
-.. code-block:: none
-
-  To grid = "lambert 614 428 12.190 -133.459 -95.0 12.19058 6367.47 25.0 N";
-
-For a Polar Stereographic grid, the syntax is
-
-.. code-block:: none
-
-  Nx Ny lat_ll lon_ll lon_orient D_km R_km lat_scale N|S
-
-Here, **Nx, Ny, lat_ll, lon_ll, lon_orient, D_km** and **R_km** have the same meaning as in the Lambert case. **lat_scale** is the latitude where the grid scale **D_km** is true, while **N|S** means to write either **N** or **S** depending on whether the stereographic projection is from the north pole or the south pole.
-
-For Plate Carrée grids, the syntax is
-
-.. code-block:: none
-
-  latlon Nx Ny lat_ll lon_ll delta_lat delta_lon
-
-The parameters **Nx, Ny, lat_ll** and **lon_ll** are as before. **delta_lat** and **delta_lon** are the latitude and longitude increments of the grid—i.e., the change in latitude or longitude between one grid point and an adjacent grid point.
-
-For a Mercator grid, the syntax is
-
-.. code-block:: none
-
-  mercator Nx Ny lat_ll lon_ll lat_ur lon_ur
-
-The parameters **Nx, Ny, lat_ll** and **lon_ll** are again as before, while **lat_ur** and **lon_ur** are the latitude and longitude of the upper right corner of the grid.
+and that will work. Failing that, you must give the parameters that specify the grid and it’s projection. Please refer the description of the grid specification strings in :ref:`appendixB`.
 
 Thankfully, the rest of the parameters in the config file are easier to specify.
 

met/docs/Users_Guide/appendixF.rst

@@ -86,7 +86,68 @@ The data must be loaded into a 2D NumPy array named **met_data**. In addition th
      }
 
 
-In the dictionary, valid time, initialization time, lead time and accumulation time (if any) must be indicated by strings. Valid and initialization times must be given in YYYYMMDD[_HH[MMSS]] format, and lead and accumulation times must be given in HH[MMSS] format, where the square brackets indicate optional elements. The dictionary must also include strings for the name, long_name, level, and units to describe the data. The rest of the **attrs** dictionary gives the grid size and projection information in the same format that is used in the netCDF files written out by the MET tools. Note that the **grid** entry in the **attrs** dictionary is itself a dictionary.
+In the dictionary, valid time, initialization time, lead time and accumulation time (if any) must be indicated by strings. Valid and initialization times must be given in YYYYMMDD[_HH[MMSS]] format, and lead and accumulation times must be given in HH[MMSS] format, where the square brackets indicate optional elements. The dictionary must also include strings for the name, long_name, level, and units to describe the data. The rest of the **attrs** dictionary gives the grid size and projection information in the same format that is used in the netCDF files written out by the MET tools. Those entries are also listed below. Note that the **grid** entry in the **attrs** dictionary is itself a dictionary.
+
+The supported grid **type** strings are described below:
+
+• **Lambert Conformal** grid dictionary entries:
+
+  • type                           ("Lambert Conformal")
+  • name                           (string)
+  • hemisphere                     (string: "N" or "S")
+  • scale_lat_1, scale_lat_2       (double)
+  • lat_pin, lon_pin, x_pin, y_pin (double)
+  • lon_orient                     (double)
+  • d_km, r_km                     (double)
+  • nx, ny                         (int)
+
+• **Polar Stereographic** grid dictionary entries:
+
+  • type                           ("Polar Stereographic")
+  • name                           (string)
+  • hemisphere                     (string: "N" or "S")
+  • scale_lat                      (double)
+  • lat_pin, lon_pin, x_pin, y_pin (double)
+  • lon_orient                     (double)
+  • d_km, r_km                     (double)
+  • nx, ny                         (int)
+
+• **Mercator** grid dictionary entries:
+
+  • type   ("Mercator")
+  • name   (string)
+  • lat_ll (double)
+  • lon_ll (double)
+  • lat_ur (double)
+  • lon_ur (double)
+  • nx, ny (int)
+
+• **LatLon** grid dictionary entries:
+
+  • type                 ("LatLon")
+  • name                 (string)
+  • lat_ll, lon_ll       (double)
+  • delta_lat, delta_lon (double)
+  • Nlat, Nlon           (int)
+
+• **Rotated LatLon** grid dictionary entries:
+
+  • type                                     ("Rotated LatLon")
+  • name                                     (string)
+  • rot_lat_ll, rot_lon_ll                   (double)
+  • delta_rot_lat, delta_rot_lon             (double)
+  • Nlat, Nlon                               (int)
+  • true_lat_south_pole, true_lon_south_pole (double)
+  • aux_rotation                             (double)
+
+• **Gaussian** grid dictionary entries:
+
+  • type     ("Gaussian")
+  • name     (string)
+  • lon_zero (double)
+  • nx, ny   (int)
+
+Additional information about supported grids can be found in :ref:`appendixB`.
 
 **Using Xarray Objects**
 

met/src/libcode/vx_grid/find_grid_by_name.cc

@@ -28,6 +28,8 @@ static bool parse_lambert_grid(const StringArray &, Grid &);
 
 static bool parse_latlon_grid(const StringArray &, Grid &);
 
+static bool parse_rotlatlon_grid(const StringArray &, Grid &);
+
 static bool parse_stereographic_grid(const StringArray &, Grid &);
 
 static bool parse_mercator_grid(const StringArray &, Grid &);
@@ -207,12 +209,13 @@ bool status = false;
    //  parse supported projection types
    //
 
-     if ( strcasecmp(grid_strings[0].c_str(), "lambert")  == 0 )  status = parse_lambert_grid(grid_strings, g);
-else if ( strcasecmp(grid_strings[0].c_str(), "latlon")   == 0 )  status = parse_latlon_grid(grid_strings, g);
-else if ( strcasecmp(grid_strings[0].c_str(), "stereo")   == 0 )  status = parse_stereographic_grid(grid_strings, g);
-else if ( strcasecmp(grid_strings[0].c_str(), "mercator") == 0 )  status = parse_mercator_grid(grid_strings, g);
-else if ( strcasecmp(grid_strings[0].c_str(), "gaussian") == 0 )  status = parse_gaussian_grid(grid_strings, g);
-else                                                              status = false;
+     if ( strcasecmp(grid_strings[0].c_str(), "lambert")   == 0 )  status = parse_lambert_grid(grid_strings, g);
+else if ( strcasecmp(grid_strings[0].c_str(), "latlon")    == 0 )  status = parse_latlon_grid(grid_strings, g);
+else if ( strcasecmp(grid_strings[0].c_str(), "rotlatlon") == 0 )  status = parse_rotlatlon_grid(grid_strings, g);
+else if ( strcasecmp(grid_strings[0].c_str(), "stereo")    == 0 )  status = parse_stereographic_grid(grid_strings, g);
+else if ( strcasecmp(grid_strings[0].c_str(), "mercator")  == 0 )  status = parse_mercator_grid(grid_strings, g);
+else if ( strcasecmp(grid_strings[0].c_str(), "gaussian")  == 0 )  status = parse_gaussian_grid(grid_strings, g);
+else                                                               status = false;
 
    //
    //  done
@@ -546,6 +549,97 @@ return ( true );
 ////////////////////////////////////////////////////////////////////////
 
 
+bool parse_rotlatlon_grid(const StringArray &grid_strings, Grid & g)
+
+{
+
+Grid * ToGrid = (Grid *) 0;
+
+RotatedLatLonData rdata;
+
+const int N = grid_strings.n_elements();
+
+if ( N != 10 )  {
+
+   mlog << Error << "\nparse_rotlatlon_grid() -> "
+        << "rotatedlatlon grid spec should have 10 entries\n\n";
+
+   exit ( 1 );
+
+}
+
+int j;
+int Nx, Ny;
+double lat_ll, lon_ll, delta_lat, delta_lon;
+double true_lat_sp, true_lon_sp, aux_rot;
+
+
+j = 1;
+
+   //
+   //  get info from the strings
+   //
+
+Nx          = atoi(grid_strings[j++].c_str());
+Ny          = atoi(grid_strings[j++].c_str());
+
+lat_ll      = atof(grid_strings[j++].c_str());
+lon_ll      = atof(grid_strings[j++].c_str());
+
+delta_lat   = atof(grid_strings[j++].c_str());
+delta_lon   = atof(grid_strings[j++].c_str());
+
+true_lat_sp = atof(grid_strings[j++].c_str());
+true_lon_sp = atof(grid_strings[j++].c_str());
+aux_rot     = atof(grid_strings[j++].c_str());
+
+   //
+   //  load up the struct
+   //
+
+rdata.name = "To (rotlatlon)";
+
+rdata.rot_lat_ll = lat_ll;
+rdata.rot_lon_ll = lon_ll;
+
+rdata.delta_rot_lat = delta_lat;
+rdata.delta_rot_lon = delta_lon;
+
+rdata.Nlat = Ny;
+rdata.Nlon = Nx;
+
+rdata.true_lat_south_pole = true_lat_sp;
+rdata.true_lon_south_pole = true_lon_sp;
+
+rdata.aux_rotation = aux_rot;
+
+if ( !west_longitude_positive )  {
+
+   rdata.rot_lon_ll *= -1.0;
+   rdata.true_lon_south_pole *= -1.0;
+
+}
+
+ToGrid = new Grid ( rdata );
+
+g = *ToGrid;
+
+if ( ToGrid )  { delete ToGrid; ToGrid = (Grid *) 0; }
+
+
+   //
+   //  done
+   //
+
+
+return ( true );
+
+}
+
+
+////////////////////////////////////////////////////////////////////////
+
+
 bool parse_mercator_grid(const StringArray &grid_strings, Grid & g)
 
 {

test/xml/unit_regrid.xml

@@ -124,6 +124,21 @@
     </output>
   </test>
 
+  <test name="regrid_data_plane_GFS_ROTLATLON_GRID_SPEC">
+    <exec>&MET_BIN;/regrid_data_plane</exec>
+    <param> \
+      &DATA_DIR_MODEL;/grib1/gfs/gfs_2012040900_F036.grib \
+      "rotlatlon 420 408 -7.542 8.326 0.035999 0.035999 -34.515 -22.179 0" \
+      &OUTPUT_DIR;/regrid/regrid_data_plane_GFS_TO_ROTLATLON_GRID_SPEC.nc \
+      -field 'name="TMP"; level="P500";' \
+      -method BILIN -width 2 \
+      -v 1
+    </param>
+    <output>
+      <grid_nc>&OUTPUT_DIR;/regrid/regrid_data_plane_GFS_TO_ROTLATLON_GRID_SPEC.nc</grid_nc>
+    </output>
+  </test>
+
   <test name="regrid_data_plane_GFS_TO_HMT_BILIN">
     <exec>&MET_BIN;/regrid_data_plane</exec>
     <param> \