Defines a Trajectory class, and a routine to extract a sub-cube along a trajectory.
In this module:
Extract a sub-cube at the given n-dimensional points.
Args:
The source Cube.
A sequence of coordinate (name) - values pairs.
Kwargs:
Request “linear” interpolation (default) or “nearest” neighbour. Only nearest neighbour is available when specifying multi-dimensional coordinates.
For example:
sample_points = [('latitude', [45, 45, 45]),
('longitude', [-60, -50, -40])]
interpolated_cube = interpolate(cube, sample_points)
A series of given waypoints with pre-calculated sample points.
- class iris.analysis.trajectory.Trajectory(waypoints, sample_count=10)¶
Bases: object
Defines a trajectory using a sequence of waypoints.
For example:
waypoints = [{'latitude': 45, 'longitude': -60}, {'latitude': 45, 'longitude': 0}] Trajectory(waypoints)Note
All the waypoint dictionaries must contain the same
coordinate names.
Args:
- waypoints
A sequence of dictionaries, mapping coordinate names to values.
Kwargs:
- sample_count
The number of sample positions to use along the trajectory.
- sampled_points = None¶
The trajectory points, as dictionaries of {coord_name: value}.
Encapsulate the operation of iris.analysis.trajectory.interpolate() with given source and target grids.
This is the type used by the UnstructuredNearest regridding scheme.
- class iris.analysis.trajectory.UnstructuredNearestNeigbourRegridder(src_cube, target_grid_cube)¶
Bases: object
A nearest-neighbour regridder to perform regridding from the source grid to the target grid.
This can then be applied to any source data with the same structure as the original ‘src_cube’.
Args:
- src_cube:
The Cube defining the source grid. The X and Y coordinates can have any shape, but must be mapped over the same cube dimensions.
- target_grid_cube:
A Cube, whose X and Y coordinates specify a desired target grid. The X and Y coordinates must be one-dimensional dimension coordinates, mapped to different dimensions. All other cube components are ignored.
- Returns:
regridder : (object)
- A callable object with the interface:
- result_cube = regridder(data)
where data is a cube with the same grid as the original src_cube, that is to be regridded to the target_grid_cube.
Note
For latitude-longitude coordinates, the nearest-neighbour distances are computed on the sphere, otherwise flat Euclidean distances are used.
The source and target X and Y coordinates must all have the same coordinate system, which may also be None. If any X and Y coordinates are latitudes or longitudes, they all must be. Otherwise, the corresponding X and Y coordinates must have the same units in the source and grid cubes.