Convert distance from scale to actual units

This function converts scale distances to actual units based on named standard_scales.

Usage

convert_dist_scale(
  dist = NULL,
  scale = NULL,
  standard = NULL,
  series = NULL,
  scale_unit = "in",
  scale_factor = NULL,
  actual_unit = NULL,
  dpi = 120,
  paper = NULL,
  orientation = NULL,
  ...
)

Arguments

dist

distance to convert. If paper is provided, dist is optional and paper width and height are used as dist.

scale

Scale name from standard_scales[["scale"]].

standard

Scale standard. Options include "USGS", "Engineering", or "Architectural".

series

Map series from standard_scales[["series"]]. Series is only available for USGS scales.

scale_unit

"mm" (converted to cm by dividing by 10), "cm", "px" (converted to inches by dividing by dpi), or "in".

scale_factor

factor for converting from scale_unit to actual_unit, e.g. if 1" = 1', the scale factor is 12. optional if scale if provided; defaults to NULL.

actual_unit

any unit supported by convert_dist_units()

dpi

dots per square inch (used as conversion factor for "px" to "in")

paper

Name of paper passed to get_paper()

orientation

Page orientation, Default: NULL. Supported options are "portrait", "landscape", or "square".

...

Arguments passed on to get_paper

name: Page name, e.g. "letter", not case sensitive, Default: NULL
width: Page width in "in", "px" or "mm" units. Default: NULL
height: Page height in "in", "px" or "mm" units. Default: NULL

Value

If paper is not provided, return a vector of dist values converted from scale_unit to actual_unit based on scale_factor or information from standard_scales data.
If paper is provided, return a data.frame with converted distances appends as columns named actual_width and actual_height.

Usage

Arguments

Value

See also