get_hfr {geocausal}

Create a hyperframe

Description

'get_hfr()' takes a dataframe with time and location variables and generates a hyperframe with point patterns. 'get_hfr()' is usually the first function that users employ in order to perform spatiotemporal causal inference analytic methods.

Usage

get_hfr(
  data,
  col,
  window,
  time_col,
  time_range,
  coordinates = c("longitude", "latitude"),
  combine = TRUE
)

Arguments

data

dataframe. The dataframe must have time and location variables. Location variables should be standard coordinates (i.e., longitudes and latitudes).

col

the name of the column for subtypes of events of interest

window

owin object (for more information, refer to 'spatstat.geom::owin()'). Basically, an owin object specifies the geographical boundaries of areas of interest.

time_col

the name of the column for time variable. Note that the time variable must be integers.

time_range

numeric vector. 'time_range' specifies the range of the time variable (i.e., min and max of the time variable). The current version assumes that the unit of this time variable is dates.

coordinates

character vector. 'coordinates' specifies the names of columns for locations. By default, 'c("longitude", "latitude")' in this order. Note that the coordinates must be in decimal degree formats.

combine

logical. 'combine' tells whether to generate output for all subtypes of events combined. By default, 'TRUE', which means that a column of ppp objects with all subtypes combined is generated in the output.

Value

A hyperframe is generated with rows representing time and columns representing the following: * The first column: time variable * The middle columns: ppp objects (see 'spatstat.geom::ppp()') generated for each subtype of events of interest * The last column (if 'combine = TRUE'): ppp objects with all subtypes combined. This column is named as 'all_combined'.

Examples

# Data
dat <- data.frame(time = c(1, 1, 2, 2),
                  longitude = c(43.9, 44.5, 44.1, 44.0),
                  latitude = c(33.6, 32.7, 33.6, 33.5),
                  type = rep(c("treat", "out"), 2))

# Hyperframe
get_hfr(data = dat,
        col = "type",
        window = iraq_window,
        time_col = "time",
        time_range = c(1, 2),
        coordinates = c("longitude", "latitude"),
        combine = FALSE)