API reference

Here we will add the documentation for selected modules.

Grid

Grid	A structured grid on a map projection.

Grid methods

Grid.extent_in_crs	Get the extent of the grid in a desired crs.
Grid.ij_to_crs	Converts local i, j to cartesian coordinates in a specified crs
Grid.map_gridded_data	Reprojects any structured data onto the local grid.
Grid.region_of_interest	Computes a region of interest (ROI).
Grid.regrid	Make a copy of the grid with an updated spatial resolution.
Grid.transform	Converts any coordinates into the local grid.

Georeferencing utils

check_crs	Checks if the crs represents a valid grid, projection or ESPG string.
proj_is_same	Checks is two pyproj projections are equal.
transform_proj	Wrapper around the pyproj.transform function.
transform_geometry	Reprojects a shapely geometry.
transform_geopandas	Reprojects a geopandas dataframe.
mercator_grid	Local transverse mercator map centered on a specified point.

Graphics

DataLevels	Assigns the right color to your data.
Map	Plotting georeferenced data.
get_cmap	Get a colormap from mpl, and also those defined by Salem.

Map & DataLevels methods

DataLevels.append_colorbar	Appends a colorbar to existing axes
DataLevels.colorbarbase	Returns a ColorbarBase to add to the cax axis.
DataLevels.set_cmap	Set a colormap.
DataLevels.set_data	Any kind of data array (also masked).
DataLevels.set_plot_params	Shortcut to all parameters related to the plot.
DataLevels.set_extend	Colorbar extensions: ‘neither’ | ‘both’ | ‘min’ | ‘max’
DataLevels.set_levels	Levels you define.
DataLevels.set_nlevels	Automatic N levels.
DataLevels.set_vmax	Maximum level value.
DataLevels.set_vmin	Mininum level value.
DataLevels.visualize	Quick plot, useful for debugging.
DataLevels.plot	Add a kind of plot of the data to an axis.

Map methods

Map.set_data	Adds data to the plot.
Map.set_contour	Adds data to contour on the map.
Map.set_contourf	Adds data to contourfill on the map.
Map.set_geometry	Adds any Shapely geometry to the map.
Map.set_lonlat_contours	Add longitude and latitude contours to the map.
Map.set_points	Shortcut for set_geometry() accepting coordinates as input.
Map.set_rgb	Manually force to a rgb img
Map.set_shapefile	Add a shapefile to the plot.
Map.set_text	Add a text to the map.
Map.set_topography	Add topographical shading to the map.

Input/output

get_demo_file	Returns the path to the desired demo file.
read_shapefile	Reads a shapefile using geopandas.
read_shapefile_to_grid	Same as read_shapefile but directly transformed to a grid.

Xarray

open_xr_dataset	Thin wrapper around xarray’s open_dataset.
open_wrf_dataset	Wrapper around xarray’s open_dataset to make WRF files a bit better.
DataArrayAccessor
DatasetAccessor

Xarray accessors

Salem adds accessors to xarray objects. They can be accessed via the .salem attribute and add the following methods (DataArray and Dataset methods are almost equivalent):

DatasetAccessor.get_map	Make a salem.Map out of the dataset.
DatasetAccessor.quick_map	Make a plot of a variable of the DataSet.
DatasetAccessor.roi	Make a region of interest (ROI) for the dataset.
DatasetAccessor.subset	Get a subset of the dataset.
DatasetAccessor.transform	Reprojects an other Dataset or DataArray onto this grid.

Old-style datasets

Old-style Datasets (prior to xarray), kept for backwards compatibility reasons and because they are quite lightweight. They might be replaced by xarray’s datasets one day.

GeoDataset	Interface for georeferenced datasets.
GeoTiff	Geolocalised tiff images (needs rasterio).
GeoNetcdf	NetCDF files with geolocalisation info.
WRF	WRF proof-of-concept template.
GoogleCenterMap	Google Static Maps (needs motionless).
GoogleVisibleMap	Google Static Maps (needs motionless).

Other

geogrid_simulator

Emulates geogrid.exe, which is useful when defining new WRF domains.