Update function arg names for plots

R/plot_slope.R

@@ -1,76 +1,83 @@
 #' Plot slope data for a 3d linestring with base R graphics
 #'
-#' @inheritParams slope_raster
-#' @inheritParams plot_dz
-#' @inheritParams sequential_dist
 #' @param route_xyz An sf linestring with x, y and z coordinates,
 #'   representing a route or other linear object.
+#' @param fill Should the profile be filled? `TRUE` by default
+#' @param horiz Should the legend be horizontal (`FALSE` by default)
+#' @param pal Color palette to use, `colorspace::diverging_hcl` by default.
+#' @param x Keyword, one of "bottomright", "bottom",
+#' "bottomleft", "left", "topleft", "top", "topright", "right" and "center"
+#' @param col Line colour, black by default
+#' @param cex Legend size, 0.9 by default
+#' @param bg Legend background colour, `grDevices::rgb(1, 1, 1, 0.8)` by default.
+#' @param title Title of the legend
+#' @param brks Breaks in colour palette to show.
+#'   `c(1, 3, 6, 10, 20, 40, 100)` by default.
+#' @param seq_brks Sequence of breaks to show in legend.
+#'   Includes negative numbers and omits zero by default
+#' @param ncol Number of columns in legend
+#' @param ... Additional parameters to pass to legend
+#' @inheritParams slope_raster
+#' @inheritParams sequential_dist
 #'
 #' @export
 #' @examples
 #' plot_slope(lisbon_route_3d)
 #' route_xyz = lisbon_road_segment_3d
 #' plot_slope(route_xyz)
-plot_slope = function(route_xyz,
-                      lonlat = sf::st_is_longlat(route_xyz),
-                      fill = TRUE,
-                      horiz = FALSE,
-                      p = colorspace::diverging_hcl,
-                      ...,
-                      x = "top",
-                      col = "black",
-                      cex = 0.9,
-                      bg = grDevices::rgb(1, 1, 1, 0.8),
-                      title = "Slope colors (percentage gradient)",
-                      s = 3:18,
-                      ncol = 4) {
+#' plot_slope(route_xyz, brks = c(1, 2, 4, 8, 16, 30))
+#' plot_slope(route_xyz, s = 5:8)
+plot_slope = function(
+  route_xyz,
+  lonlat = sf::st_is_longlat(route_xyz),
+  fill = TRUE,
+  horiz = FALSE,
+  pal =colorspace::diverging_hcl,
+  x = "top",
+  col = "black",
+  cex = 0.9,
+  bg = grDevices::rgb(1, 1, 1, 0.8),
+  title = "Slope colors (percentage gradient)",
+  brks = c(3, 6, 10, 20, 40, 100),
+  seq_brks = seq(from = 3, to = length(brks) * 2 - 2),
+  ncol = 4,
+  ...
+  ) {
   dz = distance_z(route_xyz, lonlat = lonlat)
-  plot_dz(dz$d, dz$z, fill = fill)
+  plot_dz(dz$d, dz$z, seq_brks = seq_brks, brks = brks, ...)
 }
 #' Plot a digital elevation profile based on xyz data
 #'
 #' @param d Cumulative distance
 #' @param z Elevations at points across a linestring
-#' @param p Color palette to use
-#' @param fill Should the profile be filled? `TRUE` by default
-#' @param x Keyword, one of "bottomright", "bottom",
-#' "bottomleft", "left", "topleft", "top", "topright", "right" and "center"
-#' @param col Line colour
-#' @param cex Legend size
-#' @param bg Legend background colour
-#' @param title Title of the legend
-#' @param brks Breaks in colour palette to show.
-#'   `c(1, 3, 6, 10, 20, 40, 100)` by default.
-#' @param s Sequence of numbers to show in legend
-#' @param ncol Number of columns in legend
-#' @param horiz Should the legend be horizontal (`FALSE` by default)
-#' @param ... Additional parameters to pass to legend
+#' @inherit plot_slope
 #' @examples
 #' route_xyz = lisbon_road_segment_3d
 #' m = sf::st_coordinates(route_xyz)
 #' d = cumsum(sequential_dist(m, lonlat = FALSE))
 #' d = c(0, d)
 #' z = m[, 3]
-#' # not exported
-#' # plot_dz(d, z)
-plot_dz = function(d,
-                   z,
-                   fill = TRUE,
-                   horiz = FALSE,
-                   p =  colorspace::diverging_hcl,
-                   ...,
-                   x = "top",
-                   col = "black",
-                   cex = 0.9,
-                   bg = grDevices::rgb(1, 1, 1, 0.8),
-                   title = "Slope colors (percentage gradient)",
-                   brks = c(3, 6, 10, 20, 40, 100),
-                   s = NULL,
-                   ncol = 4) {
+#' slopes:::plot_dz(d, z, brks = c(3, 6, 10, 20, 40, 100))
+plot_dz = function(
+  d,
+  z,
+  fill = TRUE,
+  horiz = FALSE,
+  pal = colorspace::diverging_hcl,
+  ...,
+  x = "top",
+  col = "black",
+  cex = 0.9,
+  bg = grDevices::rgb(1, 1, 1, 0.8),
+  title = "Slope colors (percentage gradient)",
+  brks = NULL,
+  seq_brks = NULL,
+  ncol = 4
+  ) {
   graphics::plot(d, z, type = "l", col = "brown", lwd = 2)
   if (fill) {
     b = make_breaks(brks)
-    pal = make_pal(p, b)
+    pal = make_pal(pal, b)
     g = slope_vector(x = d, elevations = z)
     colz = make_colz(g, b, pal)
     lapply(seq(d)[-(length(d))], function(i) {
@@ -82,7 +89,8 @@ plot_dz = function(d,
       )
     })
     graphics::lines(d, z, col = col, lwd = 2)
-    if(is.null(s)) s = seq(from = 3, to = length(b) - 2)
+    if(is.null(seq_brks)) seq_brks = seq(from = 3, to = length(b) - 2)
+    s = c(seq_brks[-(length(seq_brks) / 2) -1], max(seq_brks) + 1)
     graphics::legend(x = x, legend = b[s] * 100, fill = pal[s],
                      ..., bg = bg, title = title, horiz = horiz,
                      ncol = ncol, cex = cex)
@@ -99,7 +107,7 @@ distance_z = function(route_xyz, lonlat) {
 
 make_breaks = function(brks) {
   n = brks
-  n = c(-rev(n), (n))
+  n = c(-rev(n), 0, (n))
   b = n / 100
   b
 }
@@ -113,11 +121,11 @@ make_colz = function(g, b, pal) {
   as.character(colz)
 }
 
-make_pal = function(p, b) {
-  if (identical(p, colorspace::diverging_hcl)) {
-    pal = p(n = length(b) - 1, palette = "Green-Brown")
+make_pal = function(pal, b) {
+  if (identical(pal, colorspace::diverging_hcl)) {
+    pal = pal(n = length(b) - 1, palette = "Green-Brown")
   } else {
-    pal = p(n = length(b) - 1)
+    pal = pal(n = length(b) - 1)
   }
   pal
 }

tests/testthat/test-plots.R

@@ -7,12 +7,12 @@ test_that("plotting functions work", {
   b = make_breaks(brks)
   expect_equal(
     b,
-    c(-0.4, -0.2, -0.1, -0.06, -0.03, 0.03, 0.06, 0.1, 0.2, 0.4)
+    c(-0.4, -0.2, -0.1, -0.06, -0.03, 0, 0.03, 0.06, 0.1, 0.2, 0.4)
     )
   g = c(-0.05, -0.04, -0.03, -0.06, -0.02, 0.01, 0.02)
   pal = c("#004B40", "#007D6F", "#00AB9C", "#6CCFC3", "#BAEAE4", "#F6F6F6",
           "#F3DEC6", "#DBB98C", "#B98E45")
-  colz = make_colz(g = g, b = b, pal = pal)
+  colz = make_colz(g = g, b = b[b != 0], pal = pal)
   expect_equal(
     colz,
     c("#6CCFC3", "#6CCFC3", "#6CCFC3", "#00AB9C", "#BAEAE4", "#BAEAE4",