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Negative exponential decay function

Source: R/decay_exponential.R
decay_exponential.Rd

Returns a negative exponential weighting function to be used inside accessibility calculating functions.

This function is generic over any kind of numeric travel cost, such as distance, time and money.

Usage

decay_exponential(decay_value)

Arguments

decay_value

A numeric vector. The calibration parameters that, when multiplied by the travel cost, are used as the exponent of e in the negative exponential function.

Value

A function that takes a generic travel cost vector (numeric) as an input and returns a list of weight vectors (a list of numeric vectors, named after the arguments passed to the decay function).

See also

Other decay functions: decay_binary(), decay_linear(), decay_logistic(), decay_power(), decay_stepped()

Examples

if (FALSE) { # identical(tolower(Sys.getenv("NOT_CRAN")), "true")
weighting_function <- decay_exponential(decay_value = 0.1)

weighting_function(c(20, 30))

weighting_function <- decay_exponential(decay_value = c(0.1, 0.2))

weighting_function(c(20, 30))
}