R/as_proj.R

In crowcanyon/localgrid: Coordinate Reference Systems for an Arbitrary Floating Grids

#' Create CRS definition in Proj system
#'
#' This function creates a new Proj-style CRS definition from list of named
#' elements.
#'
#' @param x A list of named Proj elements
#'
#' @return A length-1 character string with the Proj-style CRS definition
#'
#' @export
#'
#' @examples
#' as_proj(
#'   list(
#'     proj = "omerc",
#'     lat_0 = 37.385,
#'     lonc = -108.51,
#'     alpha = 0,
#'     gamma = 0,
#'     k_0 = 1,
#'     x_0 = 500,
#'     y_0 = 500
#'   )
#' )
as_proj <-
  function(x) {
    x %>% {
      paste0("+", names(.), "=", ., collapse = " ")
    }
  }