Generate impedance values — generate

This function calculate the impedance (f) related to a travel cost (usually duration) by applying probability density functions (PDF).

Usage

generate_impedance(
  df,
  travel_cost_col = "travel_cost",
  distribution_col = "distribution",
  est1_col = "est_1",
  est2_col = "est_2",
  output_col = "f"
)

Arguments

df: A data frame containing columns for travel cost, distribution name, and two parameters.
travel_cost_col: Name of the column with the travel costs (numeric). Default "travel_time".
distribution_col: Name of the column with the distribution name. Default "distribution".
est1_col: Name of the column for the first distribution parameter. Default "est_1".
est2_col: Name of the column for the second distribution parameter. Default "est_2".
output_col: Name of the new column to store impedance values. Default "f".

Value

The input data frame with an additional column (output_col) containing the impedance values.

Examples

if (FALSE) { # \dontrun{
df <- data.frame(Distribution = c("lnorm", "lnorm", "gamma"),
  Est_1 = c(0.5, 0.5, 1.2),
  Est_2 = c(0.8, 0.8, 0.3),
  travel_time = c(1, 5, 10))

df_with_impedance <- generate_impedance(df, travel_cost_col = travel_time,
                                        distribution_col = Distribution,
                                        est1_col = Est_1, est2_col = Est_2)
} # }