deprivateR (version 0.1.0)

dep_map_breaks: Calculating Map Breaks

Description

Create "bins" for choropleth maps creating using either ggplot2 or leaflet. The function can create the bins automatically or will accept pre-specified breaks.

Usage

dep_map_breaks(.data, var, new_var, classes, style, breaks,
    sig_digits = 2, return = "col", show_warnings = TRUE)

Value

Either a data object (if return is "col") or a vector of breaks (if return is "breaks"). If a data object is returned, the new column will be placed directly after the input variable specified in var.

Arguments

.data

A data object, either sf, tibble, or data.frame

var

Variable breaks should be based on, can be quoted or unquoted

new_var

Optional name of new variable to store breaks in, can be quoted or unquoted. This is required if you are returning a column, but can be omitted if you are returning breaks instead of a column.

classes

Optional integer scalar; count of the number of classes to create. If you are supplying breaks manually, this can be omitted.

style

String scalar; one of the classes supported by classInt::classIntervals(). "jenks" is the ArcGIS default. "quantile" and "fisher" are better alternatives. As with classes, this can be omitted if you are supplying breaks manually.

breaks

Optional numeric vector if you want to pre-specify the cut points for your breaks. Provide the lower and upper bounds of your distribution. Any values supplied in between the bounds will be the upper bound of individual bins.

sig_digits

Integer; how many significant digits should be applied when calculating breaks and constructing labels?

return

String scalar; one of either "col" (default) or "breaks". The default behavior adds a factor containing the bins to the data object to facilitate mapping. Specifying "breaks" will return the calculated breaks instead, which can be modified and passed to the breaks argument later in a script to make the final map.

show_warnings

Logical scalar; if TRUE, warnings created by classInt::classIntervals() if NA values are identified while findings classes.

Examples

# prep data
## load sample data
ndi_m <- dep_sample_data(index = "ndi_m")

## calculate NDI with sample data
ndi_m <- dep_calc_index(ndi_m, geography = "county", index = "ndi_m", year = 2022,
  return_percentiles = TRUE)

# calculate breaks using a built-in algorithm
dep_map_breaks(ndi_m, var = "NDI_M", new_var = "map_breaks", classes = 5,
  style = "fisher")

# use manually specified breaks
## set breaks
breaks <- c(0, 25, 50, 75, max(ndi_m$NDI_M))

## calculate breaks
dep_map_breaks(ndi_m, var = "NDI_M", new_var = "map_breaks", breaks = breaks)