abstract_lut

LutDataLoader(bounds, params)

Bases: DataLoaderInterface

Abstract class for all LookUp Table Datasets.

This is where large-scale operations are performed, such as importing data, downsampling, reprojecting, and renaming variables

Parameters:

Name	Type	Description	Default
bounds	Boundary	Initial mesh boundary to limit scope of data ingest	required
params	dict	Values needed by dataloader to initialise. Unique to each dataloader	required

Attributes:

Name	Type	Description
self.data	DataFrame	Data stored by dataloader to use when called upon by the mesh. Must be saved in mercator projection (EPSG:4326), with columns 'geometry' and data_name.
self.data_name	str	Name of scalar variable. Must be the column name in the dataframe

Raises:

Type	Description
ValueError	If no data lies within the parsed boundary

add_default_params(params)

Set default values for all LUT dataloaders. This function should be overloaded to include any extra params for a specific dataloader

Parameters:

Name	Type	Description	Default
params	dict	Dictionary containing attributes that are required for each dataloader.	required

Returns:

Type	Description
dict	Dictionary of attributes the dataloader will require, completed with default values if not provided in config.

calculate_coverage(bounds, data=None)

Calculates percentage of boundary covered by dataset

Parameters:

Name	Type	Description	Default
bounds	Boundary	Boundary being compared against	required
data	DataFrame	Dataset with shapely polygons in 'geometry' column Defaults to objects internal dataset.	None

Returns:

Name	Type	Description
float		Decimal fraction of boundary covered by the dataset

downsample()

Downsampling not supported by LookUpTable Dataloader

get_data_col_name()

Retrieve name of data column. Used for when data_name not defined in params.

Returns:

Name	Type	Description
str		Name of data column

Raises:

Type	Description
AssertionError	If multiple possible data columns found, can't retrieve data name

get_hom_condition(bounds, splitting_conds, data=None)

Retrieves homogeneity condition of data within boundary.

Parameters:

Name	Type	Description	Default
bounds	Boundary	Boundary object with limits of datarange to analyse	required
splitting_conds	dict	Containing the following keys: 'boundary': (boolean) True if user wants to split when polygon boundary goes through bounds	required

Returns:

Name	Type	Description
str		The homogeniety condtion returned is of the form: 'CLR' = the boundary is completely contained within the LUT regions, no need to split 'MIN' = the boundary contains no LUT data, can't split 'HET' = the boundary contains an edge within the LUT data, should split

get_value(bounds, agg_type=None, skipna=False, data=None)

Retrieve aggregated value from within bounds

Parameters:

Name	Type	Description	Default
aggregation_type	str	Method of aggregation of datapoints within bounds. Can be upper or lower case. Accepts 'MIN', 'MAX', 'MEAN', 'MEDIAN', 'STD', 'COUNT'	required
bounds	Boundary	Boundary object with limits of lat/long	required
skipna	bool	Defines whether to propogate NaN's or not Default = False (includes NaN's)	False

Returns:

Name	Type	Description
dict		{variable (str): aggregated_value (float)} Aggregated value within bounds following aggregation_type

Raises:

Type	Description
ValueError	aggregation type not in list of available methods

import_data(bounds) abstractmethod

User defined method for importing data from files, or even generating data from scratch

Returns:

Type	Description
	pd.DataFrame: Coordinates and data being imported from file if pd.DataFrame, - Must have columns 'geometry' and data_name - Must have single data column

reproject()

Reprojection not supported by LookUpTable Dataloader

set_data_col_name(new_name)

Sets name of data column/data variable

Parameters:

Name	Type	Description	Default
name	str	Name to replace currently stored name with	required

Returns:

Type	Description
	pd.DataFrame: Data with variable name changed

trim_datapoints(bounds, data=None)

Trims datapoints from self.data within boundary defined by 'bounds'. self.data can be pd.DataFrame or xr.Dataset

Parameters:

Name	Type	Description	Default
bounds	Boundary	Limits of lat/long/time to select data from	required

Returns:

Type	Description
	pd.DataFrame: Trimmed dataset in same format as self.data

verify_data(data=None)

Verifies that all geometries read in are Polygons or MultiPolygons If MultiPolygon, then split out into multiple Polygons

Parameters:

Name	Type	Description	Default
data	DataFrame	DataFrame with at least columns 'geometry' and a variable. Defaults to dataloader's data attribute.	None

Raises:

Type	Description
ValueError	If read in a geometry that is not Polygon or MultiPolygon