From cb0e2e56127f6dedd83744e8b515581b373d4abd Mon Sep 17 00:00:00 2001
From: Robin Lovelace <rob00x@gmail.com>
Date: Fri, 3 Sep 2021 19:28:18 +0100
Subject: [PATCH] Improve docs for slope_xyz()

This fixes another issue in #20 by mentioning alternative functions that can be passed to the fun argument
---
 R/slopes.R          | 10 ++++++++++
 man/slope_raster.Rd |  2 ++
 man/slope_xyz.Rd    | 11 ++++++++++-
 3 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/R/slopes.R b/R/slopes.R
index d781eb5..05dea76 100644
--- a/R/slopes.R
+++ b/R/slopes.R
@@ -255,6 +255,14 @@ slope_raster = function(
 
 #' Extract slopes from xyz data frame or sf objects
 #'
+#' The function takes a sf object with 'XYZ' coordinates and returns a vector
+#' of numeric values representing the average slope of each linestring in the
+#' sf data frame input.
+#'
+#' The default function to calculate the mean slope is `slope_matrix_weighted()`.
+#' You can also use `slope_matrix_mean()` from the package or any other
+#' function that takes the same inputs as these functions not in the package.
+#'
 #' @param route_xyz An sf object with x, y, z dimensions
 #' @param lonlat Are the coordinates in lon/lat order? TRUE by default
 #' @inheritParams slope_raster
@@ -264,7 +272,9 @@ slope_raster = function(
 #' @examples
 #' route_xyz = lisbon_road_segment_3d
 #' slope_xyz(route_xyz, lonlat = FALSE)
+#' slope_xyz(route_xyz$geom, lonlat = FALSE)
 #' slope_xyz(route_xyz, lonlat = FALSE, directed = TRUE)
+#' slope_xyz(route_xyz, lonlat = FALSE, fun = slope_matrix_mean)
 slope_xyz = function(
   route_xyz,
   fun = slope_matrix_weighted,
diff --git a/man/slope_raster.Rd b/man/slope_raster.Rd
index da90a35..6feff4b 100644
--- a/man/slope_raster.Rd
+++ b/man/slope_raster.Rd
@@ -62,4 +62,6 @@ routes = lisbon_road_network[1:3, ]
 dem = dem_lisbon_raster
 (s = slope_raster(routes, dem))
 cor(routes$Avg_Slope, s)
+slope_raster(routes, dem, directed = TRUE)
+slope_raster(sf::st_reverse(routes), dem, directed = TRUE)
 }
diff --git a/man/slope_xyz.Rd b/man/slope_xyz.Rd
index 31327a4..6282d1f 100644
--- a/man/slope_xyz.Rd
+++ b/man/slope_xyz.Rd
@@ -28,10 +28,19 @@ A vector of slopes equal in length to the number simple features
 (rows representing linestrings) in the input object.
 }
 \description{
-Extract slopes from xyz data frame or sf objects
+The function takes a sf object with 'XYZ' coordinates and returns a vector
+of numeric values representing the average slope of each linestring in the
+sf data frame input.
+}
+\details{
+The default function to calculate the mean slope is \code{slope_matrix_weighted()}.
+You can also use \code{slope_matrix_mean()} from the package or any other
+function that takes the same inputs as these functions not in the package.
 }
 \examples{
 route_xyz = lisbon_road_segment_3d
 slope_xyz(route_xyz, lonlat = FALSE)
+slope_xyz(route_xyz$geom, lonlat = FALSE)
 slope_xyz(route_xyz, lonlat = FALSE, directed = TRUE)
+slope_xyz(route_xyz, lonlat = FALSE, fun = slope_matrix_mean)
 }