improve documentation

R/fpr_sp_assign_sf_from_utm.R

@@ -4,13 +4,17 @@
 #' easting and northing from a NAD 83 UTM Zone coordinate systems. It prepares a spatial data frame
 #' by grouping based on a specified column (UTM zone), converting to a spatial data frame, transforming
 #' the coordinate reference system, and then binding the rows back together. The returned dataframe
-#' must be in a Geographic Coordinate System (BC Albers or vs a Spatial coordinate system like UTM.
+#' must be in a Geographic Coordinate System (ex. BC Albers or WSG84 vs a Spatial coordinate system like UTM.).
+#'
+#' The reason the returned dataframe must be in a Geographic Coordinate System is to avoid issues when
+#' input points are located in different spatial zones.
 #'
 #' @param dat A data frame.
 #' @param col_utm_zone The name of the column to group by. Default is "utm_zone".
 #' @param col_easting The name of the easting coordinate column. Default is "easting".
 #' @param col_northing The name of the northing coordinate column. Default is "northing".
-#' @param crs_return Numeric. The EPSG code to transform the coordinate reference system to. Must be Geographic (ex. Albers or WSG84). Default is BC Albers - 3005.
+#' @param crs_return Numeric. The EPSG code to transform the coordinate reference system to. Must be Geographic
+#' (ex. Albers - 3005 or WSG84 - 4326). Default is BC Albers.
 #' @return A spatial data frame.
 #' @importFrom dplyr group_split bind_rows arrange
 #' @importFrom purrr map