Create a Hinge Feature — maxent_hinge

Creates a piecewise-linear hinge feature.

Usage

maxent_hinge_feature(values, name, min_knot, max_knot, reverse = FALSE)

Arguments

values: Numeric vector of environmental variable values.
name: Character string: feature name/identifier.
min_knot: Lower knot of the hinge.
max_knot: Upper knot of the hinge (must be strictly greater than min_knot).
reverse: Logical; if TRUE, use reverse hinge. Default is FALSE (forward hinge).

Value

External pointer to a HingeFeature C++ object.

Details

Forward hinge (reverse = FALSE): eval(i) = max(0, (values[i] - min_knot) / (max_knot - min_knot))

Reverse hinge (reverse = TRUE): eval(i) = max(0, (max_knot - values[i]) / (max_knot - min_knot))

Examples

vals <- c(0, 5, 10, 3)
f <- maxent_hinge_feature(vals, "temperature_hinge", min_knot = 2, max_knot = 8)
maxent_feature_eval(f, 2)  # values[2] = 5 -> (5-2)/(8-2) = 0.5
#> [1] 0.5