Now uses CoordPair for vertical cross sections so that lat/lon points can be used directly.

src/wrf/interp.py

@@ -10,7 +10,7 @@ from .extension import (_interpz3d, _vertcross, _interpline, _smooth2d,
 from .metadecorators import set_interp_metadata
 from .util import extract_vars, is_staggered, get_id, npvalues
 from .py3compat import py3range
-from .interputils import get_xy, get_xy_z_params
+from .interputils import get_xy, get_xy_z_params, to_xy_coords
 from .constants import Constants, ConversionFactors
 from .terrain import get_terrain
 from .geoht import get_height
@@ -91,6 +91,7 @@ def interplevel(field3d, vert, desiredlev, missing=Constants.DEFAULT_FILL,
 
 @set_interp_metadata("cross")
 def vertcross(field3d, vert, levels=None, missing=Constants.DEFAULT_FILL,
+              wrfin=None, timeidx=0, stagger=None, projection=None, 
               pivot_point=None, angle=None,
               start_point=None, end_point=None,
               latlon=False, cache=None, meta=True):
@@ -99,7 +100,10 @@ def vertcross(field3d, vert, levels=None, missing=Constants.DEFAULT_FILL,
     The cross section is defined by a horizontal line through the domain.  
     This horizontal line is defined by either including the 
     *pivot_point* and *angle* parameters, or the *start_point* and 
-    *end_point* parameters.
+    *end_point* parameters. The *pivot_point*, *start_point*, and *end_point* 
+    coordinates can be defined in either x,y or latitude,longitude space.  
+    If latitude,longitude coordinates are used, then a WRF input file or 
+    map projection must also be specified.
     
     The vertical levels for the cross section are fixed if *levels* is not 
     specified, and are determined by dividing the vertical coordinate in to 
@@ -124,32 +128,71 @@ def vertcross(field3d, vert, levels=None, missing=Constants.DEFAULT_FILL,
             as *field3d*
             
         levels (sequence, optional): A sequence of :obj:`float` for the desired
-            vertical levels in the output array.  If None, a fixed set of 
-            vertical levels is provided.  Default is None.
+            vertical levels in the output array.  Must be in the same units 
+            as *vert*.  If None, a fixed set of vertical levels is provided.  
+            Default is None.
             
         missing (:obj:`float`): The fill value to use for the output.  
             Default is :data:`wrf.Constants.DEFAULT_FILL`.
             
-        pivot_point (:obj:`tuple` or :obj:`list`, optional): A 
-            :obj:`tuple` or :obj:`list` with two entries, 
-            in the form of [x, y] (or [west_east, south_north]), which 
-            indicates the x,y location through which the plane will pass.  
-            Must also specify `angle`.
+        wrfin (:class:`netCDF4.Dataset`, :class:`Nio.NioFile`, or an \
+            iterable, optional): Input WRF ARW NetCDF 
+            data as a :class:`netCDF4.Dataset`, :class:`Nio.NioFile` 
+            or an iterable sequence of the aforementioned types. This is used
+            to obtain the map projection when using latitude,longitude 
+            coordinates. Default is None.
+            
+        timeidx (:obj:`int`, optional): The 
+            desired time index when obtaining map boundary information 
+            from moving nests. This value can be a positive or negative integer.
+            Only required when *wrfin* is specified and the nest is moving.
+            Currently, :data:`wrf.ALL_TIMES` is not supported.
+            Default is 0.
+            
+        stagger (:obj:`str`): If using latitude, longitude coordinate pairs 
+            for *start_point*, *end_point*, or *pivot_point*, 
+            set the appropriate grid staggering type for *field2d*. By default,
+            the mass grid is used.  The options are:
+            
+                - 'm': Use the mass grid (default).
+                - 'u': Use the same staggered grid as the u wind component, 
+                  which has a staggered west_east (x) dimension.
+                - 'v': Use the same staggered grid as the v wind component, 
+                  which has a staggered south_north (y) dimension.
+            
+        projection (:class:`wrf.WrfProj` subclass, optional): The map 
+            projection object to use when working with latitude, longitude 
+            coordinates, and must be specified if *wrfin* is None. Default 
+            is None.
+        
+        pivot_point (:class`wrf.CoordPair`, optional): A coordinate pair for 
+            the pivot point, which indicates the location through which 
+            the plane will pass. Must also specify *angle*.  The coordinate 
+            pair can be in x,y grid coordinates or latitude, longitude 
+            coordinates.  If using latitude, longitude coordinates, then 
+            either *wrfin* or *projection* must be specified to obtain the 
+            map projection.  Default is None.
         
         angle (:obj:`float`, optional): Only valid for cross sections where 
             a plane will be plotted through 
             a given point on the model domain. 0.0 represents a S-N cross 
             section.  90.0 is a W-E cross section. 
             
-        start_point (:obj:`tuple` or :obj:`list`, optional): A 
-            :obj:`tuple` or :obj:`list` with two entries, in the form of 
-            [x, y] (or [west_east, south_north]), which indicates the start 
-            x,y location through which the plane will pass.
-            
-        end_point (:obj:`tuple` or :obj:`list`, optional): A 
-            :obj:`tuple` or :obj:`list` with two entries, in the form of 
-            [x, y] (or [west_east, south_north]), which indicates the end x,y 
-            location through which the plane will pass.
+        start_point (:class:`wrf.CoordPair`, optional): A coordinate pair 
+            which indicates the start location through which the plane will 
+            pass. Must also specify *end_point*. The coordinate 
+            pair can be in x,y grid coordinates or latitude, longitude 
+            coordinates.  If using latitude, longitude coordinates, then 
+            either *wrfin* or *projection* must be specified to obtain the 
+            map projection.  Default is None.
+            
+        end_point (:class:`wrf.CoordPair`, optional): A coordinate pair 
+            which indicates the end location through which the plane will 
+            pass. Must also specify *end_point*. The coordinate 
+            pair can be in x,y grid coordinates or latitude, longitude 
+            coordinates.  If using latitude, longitude coordinates, then 
+            either *wrfin* or *projection* must be specified to obtain the 
+            map projection.  Default is None.
             
         latlon (:obj:`bool`, optional): Set to True to also interpolate the 
             two-dimensional latitude and longitude coordinates along the same 
@@ -178,6 +221,10 @@ def vertcross(field3d, vert, levels=None, missing=Constants.DEFAULT_FILL,
         :class:`numpy.ndarray` object with no metadata.
         
     """
+    if timeidx is None:
+        raise ValueError("'timeidx' must be a positive or negative integer")
+    
+    
     # Some fields like uvmet have an extra left dimension for the product
     # type, we'll handle that iteration here.
     multi = True if field3d.ndim - vert.ndim == 1 else False
@@ -187,9 +234,37 @@ def vertcross(field3d, vert, levels=None, missing=Constants.DEFAULT_FILL,
         var2dz = cache["var2dz"]
         z_var2d = cache["z_var2d"]
     except (KeyError, TypeError):
-        xy, var2dz, z_var2d = get_xy_z_params(npvalues(vert), pivot_point, 
-                                              angle, start_point, end_point,
-                                              levels)
+        # Convert Lat/Lon points to grid points
+        start_point_xy = None
+        end_point_xy = None
+        pivot_point_xy = None
+        
+        if pivot_point is not None:
+            if pivot_point.lat is not None and pivot_point.lon is not None:
+                xy_coords = to_xy_coords(pivot_point, wrfin, timeidx, 
+                                         stagger, projection)
+                pivot_point_xy = (xy_coords.x, xy_coords.y)
+            else:
+                pivot_point_xy = (pivot_point.x, pivot_point.y)
+                
+        if start_point is not None and end_point is not None:
+            if start_point.lat is not None and start_point.lon is not None:
+                xy_coords = to_xy_coords(start_point, wrfin, timeidx, 
+                                         stagger, projection)
+                start_point_xy = (xy_coords.x, xy_coords.y)
+            else:
+                start_point_xy = (start_point.x, start_point.y)
+                
+            if end_point.lat is not None and end_point.lon is not None:
+                xy_coords = to_xy_coords(end_point, wrfin, timeidx, 
+                                         stagger, projection)
+                end_point_xy = (xy_coords.x, xy_coords.y)
+            else:
+                end_point_xy = (end_point.x, end_point.y)
+                
+        xy, var2dz, z_var2d = get_xy_z_params(npvalues(vert), pivot_point_xy, 
+                                              angle, start_point_xy, 
+                                              end_point_xy, levels)
     
     if not multi:
         result = _vertcross(field3d, xy, var2dz, z_var2d, missing)
@@ -206,36 +281,84 @@ def vertcross(field3d, vert, levels=None, missing=Constants.DEFAULT_FILL,
 
 @set_interp_metadata("line")
 def interpline(field2d, pivot_point=None, 
+               wrfin=None, timeidx=0, stagger=None, projection=None,
                angle=None, start_point=None,
                end_point=None, latlon=False, 
                cache=None, meta=True):
     """Return the two-dimensional field interpolated along a line.
       
+    This line is defined by either including the 
+    *pivot_point* and *angle* parameters, or the *start_point* and 
+    *end_point* parameters. The *pivot_point*, *start_point*, and *end_point* 
+    coordinates can be defined in either x,y or latitude,longitude space.  
+    If latitude,longitude coordinates are used, then a WRF input file or 
+    map projection must also be specified.
+    
     Args:
     
         field2d (:class:`xarray.DataArray` or :class:`numpy.ndarray`):
             A two-dimensional field.
     
-        pivot_point (:obj:`tuple` or :obj:`list`, optional): A 
-            :obj:`tuple` or :obj:`list` with two entries, 
-            in the form of [x, y] (or [west_east, south_north]), which 
-            indicates the x,y location through which the plane will pass.  
-            Must also specify `angle`.
+        wrfin (:class:`netCDF4.Dataset`, :class:`Nio.NioFile`, or an \
+            iterable, optional): Input WRF ARW NetCDF 
+            data as a :class:`netCDF4.Dataset`, :class:`Nio.NioFile` 
+            or an iterable sequence of the aforementioned types. This is used
+            to obtain the map projection when using latitude,longitude 
+            coordinates. Should not be used when working with x,y 
+            coordinates. Default is None.
+            
+        timeidx (:obj:`int`, optional): The 
+            desired time index when obtaining map boundary information 
+            from moving nests. This value can be a positive or negative integer.
+            Only required when *wrfin* is specified and the nest is moving.
+            Currently, :data:`wrf.ALL_TIMES` is not supported.
+            Default is 0. 
+            
+        stagger (:obj:`str`): If using latitude, longitude coordinate pairs 
+            for *start_point*, *end_point*, or *pivot_point*, 
+            set the appropriate grid staggering type for *field2d*. By default,
+            the mass grid is used.  The options are:
+            
+                - 'm': Use the mass grid (default).
+                - 'u': Use the same staggered grid as the u wind component, 
+                  which has a staggered west_east (x) dimension.
+                - 'v': Use the same staggered grid as the v wind component, 
+                  which has a staggered south_north (y) dimension.
+            
+        projection (:class:`wrf.WrfProj`, optional): The map 
+            projection object to use when working with latitude, longitude 
+            coordinates, and must be specified if *wrfin* is None. Should 
+            not be used when working with x,y coordinates.  Default 
+            is None.
+            
+        pivot_point (:class`wrf.CoordPair`, optional): A coordinate pair for 
+            the pivot point, which indicates the location through which 
+            the plane will pass. Must also specify *angle*.  The coordinate 
+            pair can be in x,y grid coordinates or latitude, longitude 
+            coordinates.  If using latitude, longitude coordinates, then 
+            either *wrfin* or *projection* must be specified to obtain the 
+            map projection.  Default is None.
         
         angle (:obj:`float`, optional): Only valid for cross sections where 
             a plane will be plotted through 
             a given point on the model domain. 0.0 represents a S-N cross 
             section.  90.0 is a W-E cross section. 
             
-        start_point (:obj:`tuple` or :obj:`list`, optional): A 
-            :obj:`tuple` or :obj:`list` with two entries, in the form of 
-            [x, y] (or [west_east, south_north]), which indicates the start 
-            x,y location through which the plane will pass.
-            
-        end_point (:obj:`tuple` or :obj:`list`, optional): A 
-            :obj:`tuple` or :obj:`list` with two entries, in the form of 
-            [x, y] (or [west_east, south_north]), which indicates the end x,y 
-            location through which the plane will pass.
+        start_point (:class:`wrf.CoordPair`, optional): A coordinate pair 
+            which indicates the start location through which the plane will 
+            pass. Must also specify *end_point*. The coordinate 
+            pair can be in x,y grid coordinates or latitude, longitude 
+            coordinates.  If using latitude, longitude coordinates, then 
+            either *wrfin* or *projection* must be specified to obtain the 
+            map projection.  Default is None.
+            
+        end_point (:class:`wrf.CoordPair`, optional): A coordinate pair 
+            which indicates the end location through which the plane will 
+            pass. Must also specify *end_point*. The coordinate 
+            pair can be in x,y grid coordinates or latitude, longitude 
+            coordinates.  If using latitude, longitude coordinates, then 
+            either *wrfin* or *projection* must be specified to obtain the 
+            map projection.  Default is None.
             
         latlon (:obj:`bool`, optional): Set to True to also interpolate the 
             two-dimensional latitude and longitude coordinates along the same 
@@ -266,11 +389,41 @@ def interpline(field2d, pivot_point=None,
         
         
     """
+    if timeidx is None:
+        raise ValueError("'timeidx' must be a positive or negative integer")
     
     try:
         xy = cache["xy"]
     except (KeyError, TypeError):
-        xy = get_xy(field2d, pivot_point, angle, start_point, end_point)
+        start_point_xy = None
+        end_point_xy = None
+        pivot_point_xy = None
+        
+        if pivot_point is not None:
+            if pivot_point.lat is not None and pivot_point.lon is not None:
+                xy_coords = to_xy_coords(pivot_point, wrfin, timeidx, 
+                                         stagger, projection)
+                pivot_point_xy = (xy_coords.x, xy_coords.y)
+            else:
+                pivot_point_xy = (pivot_point.x, pivot_point.y)
+                
+        if start_point is not None and end_point is not None:
+            if start_point.lat is not None and start_point.lon is not None:
+                xy_coords = to_xy_coords(start_point, wrfin, timeidx, 
+                                         stagger, projection)
+                start_point_xy = (xy_coords.x, xy_coords.y)
+            else:
+                start_point_xy = (start_point.x, start_point.y)
+                
+            if end_point.lat is not None and end_point.lon is not None:
+                xy_coords = to_xy_coords(end_point, wrfin, timeidx, 
+                                         stagger, projection)
+                end_point_xy = (xy_coords.x, xy_coords.y)
+            else:
+                end_point_xy = (end_point.x, end_point.y)
+                
+        xy = get_xy(field2d, pivot_point_xy, angle, start_point_xy, 
+                    end_point_xy)
         
     return _interpline(field2d, xy)
 

src/wrf/interputils.py

@@ -2,11 +2,15 @@ from __future__ import (absolute_import, division, print_function,
                         unicode_literals)
 
 from math import floor, ceil
+from collections import Iterable
 
 import numpy as np
 
 from .extension import _interp2dxy
 from .py3compat import py3range
+from .coordpair import CoordPair
+from .constants import Constants, ProjectionTypes
+from .latlonutils import _ll_to_xy
 
 
 def to_positive_idxs(shape, coord):
@@ -256,11 +260,11 @@ def get_xy_z_params(z, pivot_point=None, angle=None,
             nlevels = int(z_max/dz)
             z_var2d = np.zeros((nlevels), dtype=z.dtype)
             z_var2d[0] = z_min
-    else:
-        z_var2d = np.asarray(levels)
             
         for i in py3range(1,nlevels):
             z_var2d[i] = z_var2d[0] + i*dz
+    else:
+        z_var2d = np.asarray(levels, z.dtype)
         
     return xy, var2dz, z_var2d
 
@@ -323,3 +327,107 @@ def get_xy(var, pivot_point=None, angle=None,
     xy = _calc_xy(xdim, ydim, pos_pivot, angle, pos_start, pos_end)
     
     return xy
+
+def to_xy_coords(pairs, wrfin=None, timeidx=0, stagger=None, projection=None):
+    """Return the coordinate pairs in grid space.
+    
+    This function converts latitude,longitude coordinate pairs to 
+    x,y coordinate pairs.
+    
+    Args:
+    
+        pairs (:class:`CoordPair` or sequence): A single coordinate pair or 
+            a sequence of coordinate pairs to be converted.
+        
+        wrfin (:class:`netCDF4.Dataset`, :class:`Nio.NioFile`, or an \
+            iterable, optional): Input WRF ARW NetCDF 
+            data as a :class:`netCDF4.Dataset`, :class:`Nio.NioFile` 
+            or an iterable sequence of the aforementioned types. This is used
+            to obtain the map projection when using latitude,longitude 
+            coordinates. Should not be used when working with x,y 
+            coordinates. Default is None.
+            
+        timeidx (:obj:`int` or :data:`wrf.ALL_TIMES`, optional): The 
+            desired time index when obtaining map boundary information 
+            from moving nests. This value can be a positive integer, 
+            negative integer, or 
+            :data:`wrf.ALL_TIMES` (an alias for None) to return 
+            all times in the file or sequence. Only required when 
+            *wrfin* is specified and the nest is moving.  Default is 0.
+            
+        stagger (:obj:`str`): If using latitude, longitude coordinate pairs 
+            for *start_point*, *end_point*, or *pivot_point*, 
+            set the appropriate grid staggering type for *field2d*. By default,
+            the mass grid is used.  The options are:
+            
+                - 'm': Use the mass grid (default).
+                - 'u': Use the same staggered grid as the u wind component, 
+                  which has a staggered west_east (x) dimension.
+                - 'v': Use the same staggered grid as the v wind component, 
+                  which has a staggered south_north (y) dimension.
+            
+        projection (:class:`wrf.WrfProj`, optional): The map 
+            projection object to use when working with latitude, longitude 
+            coordinates, and must be specified if *wrfin* is None. Default 
+            is None.
+                    
+    Returns:
+        
+        :class:`wrf.CoordPair` or sequence: The coordinate pair(s) in 
+        x,y grid coordinates.
+        
+    """
+    
+    if wrfin is None and projection is None:
+        raise ValueError ("'wrfin' or 'projection' parameter is required")
+    
+    if isinstance(pairs, Iterable):
+        lat = [pair.lat for pair in pairs]
+        lon = [pair.lon for pair in pairs]
+    else:
+        lat = pairs.lat
+        lon = pairs.lon
+        
+    if wrfin is not None:
+        xy_vals = _ll_to_xy(lat, lon, wrfin=wrfin, timeidx=timeidx,  
+             squeeze=True, meta=False, stagger=stagger, as_int=True)
+        
+    else:
+        map_proj = projection.map_proj
+        
+        if map_proj == ProjectionTypes.LAT_LON:
+            pole_lat = projection.pole_lat
+            pole_lon = projection.pole_lon
+            latinc = ((projection.dy*360.0)/2.0 / 
+                      Constants.PI/Constants.WRF_EARTH_RADIUS)
+            loninc = ((projection.dx*360.0)/2.0 / 
+                      Constants.PI/Constants.WRF_EARTH_RADIUS)
+        else:
+            pole_lat = 90.0
+            pole_lon = 0.0
+            latinc = 0.0
+            loninc = 0.0
+
+        
+        xy_vals = _ll_to_xy(lat, lon, meta=False, squeeze=True, 
+                                as_int=True,
+                                map_proj=projection.map_proj, 
+                                truelat1=projection.truelat1, 
+                                truelat2=projection.truelat2, 
+                                stand_lon=projection.stand_lon, 
+                                ref_lat=projection.ll_lat, 
+                                ref_lon=projection.ll_lon, 
+                                pole_lat=pole_lat, 
+                                pole_lon=pole_lon, 
+                                known_x=0, 
+                                known_y=0, 
+                                dx=projection.dx, 
+                                dy=projection.dy, 
+                                latinc=latinc, 
+                                loninc=loninc)
+ 
+    if xy_vals.ndim == 1:
+        return CoordPair(x=xy_vals[0], y=xy_vals[1])
+    else:
+        return [CoordPair(x=xy_vals[0,i], y=xy_vals[1,i]) 
+                for i in py3range(xy_vals.shape[1])]

src/wrf/latlon.py

@@ -290,11 +290,17 @@ def ll_to_xy_proj(latitude, longitude, meta=True, squeeze=True, as_int=True,
         dy (:obj:`float`) - The y spacing in meters at the true latitude.  
             Required for *map_proj* = 1, 2, 3 (defaults to 0 otherwise).
         
-        latinc (:obj:`float`): The lower left corner latitude at (0,0).
-            Required for *map_proj* = 6.
+        latinc (:obj:`float`): Required for *map_proj* = 6. Defined as:
             
-        loninc (:obj:`float`) - The lower left corner longitude at (0,0).
-            Required for *map_proj* = 6.
+            .. code-block:: python
+            
+                latinc = (dy*360.0)/2.0/Constants.PI/Constants.WRF_EARTH_RADIUS
+        
+        loninc (:obj:`float`): Required for *map_proj* = 6. Defined as:
+            
+            .. code-block:: python
+            
+                loninc = (dx*360.0)/2.0/Constants.PI/Constants.WRF_EARTH_RADIUS
 
     Returns:
         :class:`xarray.DataArray` or :class:`numpy.ndarray`: The 
@@ -450,11 +456,17 @@ def xy_to_ll_proj(x, y, meta=True, squeeze=True, map_proj=None, truelat1=None,
         dy (:obj:`float`) - The y spacing in meters at the true latitude.  
             Required for *map_proj* = 1, 2, 3 (defaults to 0 otherwise).
         
-        latinc (:obj:`float`): The lower left corner latitude at (0,0).
-            Required for *map_proj* = 6.
+        latinc (:obj:`float`): Required for *map_proj* = 6. Defined as:
+            
+            .. code-block:: python
+            
+                latinc = (dy*360.0)/2.0/Constants.PI/Constants.WRF_EARTH_RADIUS
+        
+        loninc (:obj:`float`): Required for *map_proj* = 6. Defined as:
             
-        loninc (:obj:`float`) - The lower left corner longitude at (0,0).
-            Required for *map_proj* = 6.
+            .. code-block:: python
+            
+                loninc = (dx*360.0)/2.0/Constants.PI/Constants.WRF_EARTH_RADIUS
 
     Returns:
         :class:`xarray.DataArray` or :class:`numpy.ndarray`: The 
@@ -475,3 +487,8 @@ def xy_to_ll_proj(x, y, meta=True, squeeze=True, map_proj=None, truelat1=None,
 
     
     
+    
+    
+    
+    
+    

src/wrf/latlonutils.py

@@ -11,6 +11,8 @@ from .util import (extract_vars, extract_global_attrs,
                    either, is_moving_domain, is_multi_time_req,
                    iter_left_indexes, is_mapping, is_multi_file)
 from .py3compat import viewkeys, viewitems
+from .projutils import dict_keys_to_upper
+ 
 
 def _lat_varname(wrfin, stagger):
     """Return the latitude variable name for the specified stagger type.
@@ -194,20 +196,6 @@ def _get_proj_params(wrfin, timeidx, stagger, method, squeeze, cache, _key):
             pole_lat, pole_lon, known_x, known_y, dx, dy, latinc, loninc)
        
 
-def _dict_keys_to_upper(d):
-    """Return a dictionary with the keys changed to uppercase.
-    
-    Args:
-        
-        d (:obj:`dict`): A dictionary.
-        
-    Returns:
-    
-        :obj:`dict`: A dictionary with uppercase keys.
-    
-    """
-    return {key.upper(): val for key, val in viewitems(d)}        
-
 # known_x and known_y are 0-based
 def _kwarg_proj_params(**projparams):
     """Return the map projection parameters.
@@ -224,7 +212,7 @@ def _kwarg_proj_params(**projparams):
         :obj:`tuple`: The map projection parameters.
     
     """
-    projparams = _dict_keys_to_upper(projparams)
+    projparams = dict_keys_to_upper(projparams)
     
     map_proj = projparams.get("MAP_PROJ")
     truelat1 = projparams.get("TRUELAT1")
@@ -609,3 +597,8 @@ def _xy_to_ll(x, y, wrfin=None, timeidx=0, stagger=None,
                       loninc, x_val, y_val)
         
     return result
+
+
+
+        
+        

src/wrf/metadecorators.py

@@ -12,7 +12,7 @@ from .util import (extract_vars, either, from_args, arg_location,
                    from_var, iter_left_indexes)
 from .coordpair import CoordPair
 from .py3compat import viewkeys, viewitems, py3range, ucode
-from .interputils import get_xy_z_params, get_xy
+from .interputils import get_xy_z_params, get_xy, to_xy_coords
 from .config import xarray_enabled
 
 if xarray_enabled():
@@ -830,7 +830,9 @@ def _set_cross_meta(wrapped, instance, args, kwargs):
         :mod:`wrapt`
         
     """  
-    argvars = from_args(wrapped, ("field3d", "vert", "latlon", "missing", 
+    argvars = from_args(wrapped, ("field3d", "vert", "levels", 
+                                  "latlon", "missing", 
+                                  "wrfin", "timeidx", "stagger", "projection",
                                   "pivot_point", "angle",
                                   "start_point", "end_point",
                                   "cache"), 
@@ -838,16 +840,48 @@ def _set_cross_meta(wrapped, instance, args, kwargs):
     
     field3d = argvars["field3d"]
     z = argvars["vert"]
+    levels = argvars["levels"]
     inc_latlon = argvars["latlon"]
     missingval = argvars["missing"]
+    wrfin = argvars["wrfin"]
+    timeidx = argvars["timeidx"]
+    stagger = argvars["stagger"]
+    projection = argvars["projection"]
     pivot_point = argvars["pivot_point"]
     angle = argvars["angle"]
     start_point = argvars["start_point"]
     end_point = argvars["end_point"]
     cache = argvars["cache"]
     
-    xy, var2dz, z_var2d = get_xy_z_params(npvalues(z), pivot_point, angle,
-              start_point, end_point)
+    start_point_xy = None
+    end_point_xy = None
+    pivot_point_xy = None
+    
+    if pivot_point is not None:
+        if pivot_point.lat is not None and pivot_point.lon is not None:
+            xy_coords = to_xy_coords(pivot_point, wrfin, timeidx, 
+                                     stagger, projection)
+            pivot_point_xy = (xy_coords.x, xy_coords.y)
+        else:
+            pivot_point_xy = (pivot_point.x, pivot_point.y)
+            
+    if start_point is not None and end_point is not None:
+        if start_point.lat is not None and start_point.lon is not None:
+            xy_coords = to_xy_coords(start_point, wrfin, timeidx, 
+                                     stagger, projection)
+            start_point_xy = (xy_coords.x, xy_coords.y)
+        else:
+            start_point_xy = (start_point.x, start_point.y)
+            
+        if end_point.lat is not None and end_point.lon is not None:
+            xy_coords = to_xy_coords(end_point, wrfin, timeidx, 
+                                     stagger, projection)
+            end_point_xy = (xy_coords.x, xy_coords.y)
+        else:
+            end_point_xy = (end_point.x, end_point.y)
+    
+    xy, var2dz, z_var2d = get_xy_z_params(npvalues(z), pivot_point_xy, angle,
+              start_point_xy, end_point_xy, levels)
     
     # Make a copy so we don't modify a user supplied cache
     if cache is not None:
@@ -877,8 +911,7 @@ def _set_cross_meta(wrapped, instance, args, kwargs):
     ed_x = xy[-1,0]
     ed_y = xy[-1,1]
     
-    cross_str = "({0}, {1}) to ({2}, {3})".format(st_x, st_y, 
-                                                               ed_x, ed_y)
+    cross_str = "({0}, {1}) to ({2}, {3})".format(st_x, st_y, ed_x, ed_y)
     if angle is not None:
         cross_str += " ; center={0} ; angle={1}".format(pivot_point,
                                                         angle)
@@ -1009,12 +1042,18 @@ def _set_line_meta(wrapped, instance, args, kwargs):
         :mod:`wrapt`
         
     """   
-    argvars = from_args(wrapped, ("field2d", "pivot_point", "angle",
+    argvars = from_args(wrapped, ("field2d", 
+                                  "wrfin", "timeidx", "stagger", "projection",
+                                  "pivot_point", "angle",
                                   "start_point", "end_point", "latlon", 
                                   "cache"), 
                           *args, **kwargs)  
     
     field2d = argvars["field2d"]
+    wrfin = argvars["wrfin"]
+    timeidx = argvars["timeidx"]
+    stagger = argvars["stagger"]
+    projection = argvars["projection"]
     pivot_point = argvars["pivot_point"]
     angle = argvars["angle"]
     start_point = argvars["start_point"]
@@ -1025,7 +1064,35 @@ def _set_line_meta(wrapped, instance, args, kwargs):
     if cache is None:
         cache = {}
         
-    xy = get_xy(field2d, pivot_point, angle, start_point, end_point)
+    start_point_xy = None
+    end_point_xy = None
+    pivot_point_xy = None
+        
+    if pivot_point is not None:
+        if pivot_point.lat is not None and pivot_point.lon is not None:
+            xy_coords = to_xy_coords(pivot_point, wrfin, timeidx, 
+                                     stagger, projection)
+            pivot_point_xy = (xy_coords.x, xy_coords.y)
+        else:
+            pivot_point_xy = (pivot_point.x, pivot_point.y)      
+    
+            
+    if start_point is not None and end_point is not None:
+        if start_point.lat is not None and start_point.lon is not None:
+            xy_coords = to_xy_coords(start_point, wrfin, timeidx, 
+                                     stagger, projection)
+            start_point_xy = (xy_coords.x, xy_coords.y)
+        else:
+            start_point_xy = (start_point.x, start_point.y)
+            
+        if end_point.lat is not None and end_point.lon is not None:
+            xy_coords = to_xy_coords(end_point, wrfin, timeidx, 
+                                     stagger, projection)
+            end_point_xy = (xy_coords.x, xy_coords.y)
+        else:
+            end_point_xy = (end_point.x, end_point.y)
+    
+    xy = get_xy(field2d, pivot_point_xy, angle, start_point_xy, end_point_xy)
     
     # Make a copy so we don't modify a user supplied cache
     new_cache = dict(cache) 
@@ -1050,8 +1117,7 @@ def _set_line_meta(wrapped, instance, args, kwargs):
     ed_x = xy[-1,0]
     ed_y = xy[-1,1]
     
-    cross_str = "({0}, {1}) to ({2}, {3})".format(st_x, st_y, 
-                                                ed_x, ed_y)
+    cross_str = "({0}, {1}) to ({2}, {3})".format(st_x, st_y, ed_x, ed_y)
     if angle is not None:
         cross_str += " ; center={0} ; angle={1}".format(pivot_point,
                                                         angle)

src/wrf/projection.py

@@ -3,8 +3,10 @@ from __future__ import (absolute_import, division, print_function,
 import numpy as np
 import math
 
+from .coordpair import CoordPair
 from .config import basemap_enabled, cartopy_enabled, pyngl_enabled
 from .constants import Constants, ProjectionTypes
+from .projutils import dict_keys_to_upper
 
 if cartopy_enabled():
     from cartopy import crs
@@ -78,6 +80,7 @@ if cartopy_enabled():
             
             self._threshold = np.diff(self.x_limits)[0] / 720
 
+
 def _ismissing(val):
     """Return True if a value is None, greater than 90.0, or less than -90.
     
@@ -95,6 +98,7 @@ def _ismissing(val):
     """
     return val is None or val > 90. or val < -90.
 
+
 class WrfProj(object):
     """A base class for storing map projection information from WRF data.
     
@@ -117,6 +121,25 @@ class WrfProj(object):
         
         top_right (indexable sequence): A pair of (ur_lat, ur_lon).
         
+        map_proj (:obj:`int`): Model projection integer id.
+        
+        truelat1 (:obj:`float`): True latitude 1.  
+        
+        truelat2 (:obj:`float`): True latitude 2.  
+        
+        moad_cen_lat (:obj:`float`): Mother of all domains center latitude.
+        
+        stand_lon (:obj:`float`): Standard longitude. 
+        
+        pole_lat (:obj:`float`): The pole latitude.
+        
+        pole_lon (:obj:`float`): The pole longitude.
+        
+        dx (:obj:`float`): The x grid spacing.
+        
+        dy (:obj:`float`): The y grid spacing.
+          
+    
     """
     def __init__(self, bottom_left=None, top_right=None, 
                  lats=None, lons=None, **proj_params):
@@ -124,13 +147,13 @@ class WrfProj(object):
         
         Args:
         
-            bottom_left (indexable sequence, optional): The lower left corner 
-                as a (latitude, longitude) pair. Must also specify *top_right* 
-                if used.  Default is None.
+            bottom_left (:class:`wrf.CoordPair`, optional): The lower left 
+                corner. Must also specify *top_right* if used.  
+                Default is None.
                 
-            top_right (indexable sequence): The upper right corner as a 
-                (latitude, longitude) pair.  Must also specify *bottom_left*
-                if used.  Default is None.
+            top_right (:class:`wrf.CoordPair`, optional): The upper right 
+                corner. Must also specify *bottom_left* if used.  
+                Default is None.
                 
             lats (:class:`numpy.ndarray`, optional): An array of at least 
                 two dimensions containing all of the latitude values.  Must 
@@ -142,11 +165,9 @@ class WrfProj(object):
                 
             **proj_params:  Map projection optional keyword arguments, that
                 have the same names as found in WRF output NetCDF global 
-                attributes:
+                attributes (case insensitive):
                 
                 - 'MAP_PROJ': The map projection type as an integer.
-                - 'CEN_LAT': Center latitude.
-                - 'CEN_LON': Center longitude.
                 - 'TRUELAT1': True latitude 1.
                 - 'TRUELAT2': True latitude 2.
                 - 'MOAD_CEN_LAT': Mother of all domains center latitude.
@@ -157,10 +178,10 @@ class WrfProj(object):
         """
         
         if bottom_left is not None and top_right is not None:
-            self.ll_lat = bottom_left[0]
-            self.ll_lon = bottom_left[1]
-            self.ur_lat = top_right[0]
-            self.ur_lon = top_right[1]
+            self.ll_lat = bottom_left.lat
+            self.ll_lon = bottom_left.lon
+            self.ur_lat = top_right.lat
+            self.ur_lon = top_right.lon
             self.bottom_left = bottom_left
             self.top_right = top_right
         elif lats is not None and lons is not None:
@@ -168,24 +189,33 @@ class WrfProj(object):
             self.ur_lat = lats[-1,-1]
             self.ll_lon = lons[0,0]
             self.ur_lon = lons[-1,-1]
-            self.bottom_left = [self.ll_lat, self.ll_lon]
-            self.top_right = [self.ur_lat, self.ur_lon]
+            self.bottom_left = CoordPair(lat=self.ll_lat, lon=self.ll_lon)
+            self.top_right = CoordPair(self.ur_lat, self.ur_lon)
         else:
             raise ValueError("invalid corner point arguments")
         
+        
+        up_proj_params = dict_keys_to_upper(proj_params)
+        
+        self.map_proj = up_proj_params.get("MAP_PROJ", None)
+        
         # These indicate the center of the nest/domain, not necessarily the 
         # center of the projection
-        self._cen_lat = proj_params.get("CEN_LAT", None)
-        self._cen_lon = proj_params.get("CEN_LON", None)
+        self._cen_lat = up_proj_params.get("CEN_LAT", None)
+        self._cen_lon = up_proj_params.get("CEN_LON", None)
         
-        self.truelat1 = proj_params.get("TRUELAT1", None)
-        self.truelat2 = (proj_params.get("TRUELAT2", None)
-                         if not _ismissing(proj_params.get("TRUELAT2", None)) 
+        self.truelat1 = up_proj_params.get("TRUELAT1", None)
+        self.truelat2 = (up_proj_params.get("TRUELAT2", None)
+                         if not _ismissing(up_proj_params.get("TRUELAT2", 
+                                                              None)) 
                          else None)
-        self.moad_cen_lat = proj_params.get("MOAD_CEN_LAT", None)
-        self.stand_lon = proj_params.get("STAND_LON", None)
-        self.pole_lat = proj_params.get("POLE_LAT", None)
-        self.pole_lon = proj_params.get("POLE_LON", None)
+        self.moad_cen_lat = up_proj_params.get("MOAD_CEN_LAT", None)
+        self.stand_lon = up_proj_params.get("STAND_LON", None)
+        self.pole_lat = up_proj_params.get("POLE_LAT", None)
+        self.pole_lon = up_proj_params.get("POLE_LON", None)
+        
+        self.dx = up_proj_params.get("DX", None)
+        self.dy = up_proj_params.get("DY", None)
         
         # Just in case...
         if self.moad_cen_lat is None:
@@ -194,6 +224,7 @@ class WrfProj(object):
         if self.stand_lon is None:
             self.stand_lon = self._cen_lon
             
+            
     def _basemap(self, resolution='l'):
         return None
     
@@ -396,8 +427,6 @@ class LambertConformal(WrfProj):
                 have the same names as found in WRF output NetCDF global 
                 attributes:
                 
-                - 'CEN_LAT': Center latitude.
-                - 'CEN_LON': Center longitude.
                 - 'TRUELAT1': True latitude 1.
                 - 'TRUELAT2': True latitude 2.
                 - 'MOAD_CEN_LAT': Mother of all domains center latitude.
@@ -542,8 +571,6 @@ class Mercator(WrfProj):
                 have the same names as found in WRF output NetCDF global 
                 attributes:
                 
-                - 'CEN_LAT': Center latitude.
-                - 'CEN_LON': Center longitude.
                 - 'TRUELAT1': True latitude 1.
                 - 'TRUELAT2': True latitude 2.
                 - 'MOAD_CEN_LAT': Mother of all domains center latitude.
@@ -686,8 +713,6 @@ class PolarStereographic(WrfProj):
                 have the same names as found in WRF output NetCDF global 
                 attributes:
                 
-                - 'CEN_LAT': Center latitude.
-                - 'CEN_LON': Center longitude.
                 - 'TRUELAT1': True latitude 1.
                 - 'TRUELAT2': True latitude 2.
                 - 'MOAD_CEN_LAT': Mother of all domains center latitude.
@@ -828,8 +853,6 @@ class LatLon(WrfProj):
                 have the same names as found in WRF output NetCDF global 
                 attributes:
                 
-                - 'CEN_LAT': Center latitude.
-                - 'CEN_LON': Center longitude.
                 - 'TRUELAT1': True latitude 1.
                 - 'TRUELAT2': True latitude 2.
                 - 'MOAD_CEN_LAT': Mother of all domains center latitude.
@@ -971,8 +994,6 @@ class RotatedLatLon(WrfProj):
                 have the same names as found in WRF output NetCDF global 
                 attributes:
                 
-                - 'CEN_LAT': Center latitude.
-                - 'CEN_LON': Center longitude.
                 - 'TRUELAT1': True latitude 1.
                 - 'TRUELAT2': True latitude 2.
                 - 'MOAD_CEN_LAT': Mother of all domains center latitude.
@@ -1120,13 +1141,13 @@ def getproj(bottom_left=None, top_right=None,
     
     Args:
         
-        bottom_left (indexable sequence, optional): The lower left corner as 
-            a (latitude, longitude) pair. Must also specify *top_right* if 
-            used.  Default is None.
+        bottom_left (:class:`wrf.CoordPair`, optional): The lower left 
+            corner. Must also specify *top_right* if used.  
+            Default is None.
                 
-        top_right (indexable sequence): The upper right corner as a 
-            (latitude, longitude) pair.  Must also specify *bottom_left*
-            if used.  Default is None.
+        top_right (:class:`wrf.CoordPair`, optional): The upper right 
+            corner. Must also specify *bottom_left* if used.  
+            Default is None.
             
         lats (:class:`numpy.ndarray`, optional): An array of at least 
             two dimensions containing all of the latitude values.  Must 
@@ -1141,8 +1162,6 @@ def getproj(bottom_left=None, top_right=None,
             attributes:
             
             - 'MAP_PROJ': The map projection type as an integer.
-            - 'CEN_LAT': Center latitude.
-            - 'CEN_LON': Center longitude.
             - 'TRUELAT1': True latitude 1.
             - 'TRUELAT2': True latitude 2.
             - 'MOAD_CEN_LAT': Mother of all domains center latitude.
@@ -1157,7 +1176,9 @@ def getproj(bottom_left=None, top_right=None,
     
     """
     
-    proj_type = proj_params.get("MAP_PROJ", 0)
+    up_proj_params = dict_keys_to_upper(proj_params)
+    
+    proj_type = up_proj_params.get("MAP_PROJ", 0)
     if proj_type == ProjectionTypes.LAMBERT_CONFORMAL:
         return LambertConformal(bottom_left, top_right, 
                                 lats, lons, **proj_params)
@@ -1169,8 +1190,8 @@ def getproj(bottom_left=None, top_right=None,
                         lats, lons, **proj_params)
     elif (proj_type == ProjectionTypes.ZERO or 
           proj_type == ProjectionTypes.LAT_LON):
-        if (proj_params.get("POLE_LAT", None) == 90. 
-            and proj_params.get("POLE_LON", None) == 0.):
+        if (up_proj_params.get("POLE_LAT", None) == 90. 
+            and up_proj_params.get("POLE_LON", None) == 0.):
             return LatLon(bottom_left, top_right, 
                           lats, lons, **proj_params)
         else:

src/wrf/projutils.py

@@ -0,0 +1,18 @@
+from __future__ import (absolute_import, division, print_function, 
+                        unicode_literals)
+
+from .py3compat import viewitems
+
+def dict_keys_to_upper(d):
+    """Return a dictionary with the keys changed to uppercase.
+    
+    Args:
+        
+        d (:obj:`dict`): A dictionary.
+        
+    Returns:
+    
+        :obj:`dict`: A dictionary with uppercase keys.
+    
+    """
+    return {key.upper() : val for key, val in viewitems(d)}

src/wrf/py3compat.py

@@ -166,3 +166,5 @@ def ucode(*args, **kwargs):
         return str(*args, **kwargs)
     
     return unicode(*args, **kwargs)
+
+

src/wrf/util.py

@@ -2596,7 +2596,8 @@ def get_proj_params(wrfin, timeidx=0, varname=None):
                                                 "CEN_LAT", "CEN_LON",
                                                 "TRUELAT1", "TRUELAT2",
                                                 "MOAD_CEN_LAT", "STAND_LON", 
-                                                "POLE_LAT", "POLE_LON"))
+                                                "POLE_LAT", "POLE_LON",
+                                                "DX", "DY"))
     multitime = is_multi_time_req(timeidx)
     if not multitime:
         time_idx_or_slice = timeidx
@@ -2947,6 +2948,13 @@ def get_id(obj):
 
 
         
+    
+    
+    
+    
+    
+    
+