conditions: Define metric conditions

View source: R/metrics_filter.R

conditionsR Documentation

Define metric conditions

Description

Helper function to define patch conditions within generate_points() or metric conditions within metrics_filter().

Usage

conditions(...)

Arguments

...

Patch or metric conditions in the form of lists. See Details.

Details

Conditions must be defined as lists (one or more).

For patch conditions, within the environment of generate_points(), each element within the list defines the condition that the patch must meet in relation to the value of certain patch-level metric, as follows:

 list(class, metric, minimum value, maximum value)
  • class: the class (raster value) of the patch that must meet the defined conditions. More than one class can be specified.

  • metric: the patch-level metric whose values must meet the defined conditions. Only one metric per condition can be defined. Available patch-level metrics can be found in metrics_list() and in documentation of the package landscapemetrics().

  • minimum value: the minimum value that the metric must have for the retained patches. If equal to -Inf, and a maximum value is defined, patches whose values in the defined metric are equal or lower to the maximum value will be retained.

  • maximum value: the maximum value that the metric must have in the retained patches. If equal to Inf, and a minimum value is defined, patches whose values in the defined metric are equal or higher to the minimum value will be retained.

For metric conditions, within the environment of metrics_filter(), each element within the list defines the required metric conditions, as follows:

 list(rasterlayers, class, radii, metric, minimum value, maximum value)
  • rasterlayers: the rasterlayers to be considered. If NA, all rasterlayers will be considered. If an extra rasterlayer must be specified, the string "ext" must precede the rasterlayer number (e.g. "ext1", "ext2").

  • class: the classes to be considered, as numbers or strings with the names of the classes. If NA, all classes of required rasterlayers will be considered. If NULL, the function will assume that the metric to be considered is a landscape-level metric. Take into account that metrics from extra calculations are considered as landscape-level metrics.

  • radii: the radii to be considered. If NA, all radii will be considered.

  • metrics: the name of the metric to be considered (as defined with its abbreviation by column "metric" in metrics_list()). Only one metric per condition can be defined. Metrics as extra calculations for extra rasterlayers must be provided as "fun_" + the name of the function (e.g. "fun_mean").

  • minimum value: the minimum value that the metric must have in the filtered landscapes. If equal to -Inf, and a maximum value is defined, landscapes whose values in the defined metric are equal or lower to the maximum value will be retained.

  • maximum value: the maximum value that the metric must have in the filtered landscapes. If equal to Inf, and a minimum value is defined, landscapes whose values in the defined metric are equal or higher to the minimum value will be retained.

See the example sections of functions generate_points() and metrics_filter() for more details.

Value

A list to be inputted within the argument patch_conditions in generate_points() or the argument conditions in metrics_filter().


phuais/multilandR documentation built on May 14, 2024, 9:11 p.m.