secondary y-axis

NAMESPACE

@@ -31,6 +31,7 @@ export(ax_title)
 export(ax_tooltip)
 export(ax_xaxis)
 export(ax_yaxis)
+export(ax_yaxis2)
 export(bar_opts)
 export(events_opts)
 export(heatmap_opts)

R/apex-utils.R

@@ -1156,10 +1156,54 @@ ax_yaxis <- function(ax,
                      crosshairs = NULL,
                      ...) {
   params <- c(as.list(environment()), list(...))[-1]
-  .ax_opt2(ax, "yaxis", l = dropNulls(params))
+  yaxis <- .get_ax_opt(ax, "yaxis")
+  if (inherits(yaxis, "yaxis2")) {
+    yaxis[[1]] <- dropNulls(params)
+  } else {
+    yaxis <- dropNulls(params)
+    class(yaxis) <- c(class(yaxis), "yaxis1")
+  }
+  .ax_opt2(ax, "yaxis", l = yaxis)
 }
 
 
+#' Secondary Y-axis options
+#'
+#' @param ax A \code{apexcharts} \code{htmlwidget} object. 
+#' @param ... See arguments from \code{\link{ax_yaxis}}.
+#'
+#' @return A \code{apexcharts} \code{htmlwidget} object.
+#' @export
+#'
+#' @examples
+#' 
+#' library(dplyr)
+#' data("economics_long", package = "ggplot2")
+#' 
+#' eco <- economics_long %>% 
+#'   filter(variable %in% c("pce", "pop")) %>% 
+#'   filter(date >= "2000-01-01")
+#' 
+#' apex(eco, aes(x = date, y = value, color = variable), type = "line") %>% 
+#'   ax_yaxis(title = list(text = "Pce")) %>% 
+#'   ax_yaxis2(opposite = TRUE, title = list(text = "Pop"))
+#'   
+ax_yaxis2 <- function(ax, ...) {
+  params <- dropNulls(list(...))
+  yaxis <- .get_ax_opt(ax, "yaxis")
+  if (inherits(yaxis, "yaxis2")) {
+    yaxis[[2]] <- params
+  } else {
+    yaxis <- list(yaxis, params)
+    class(yaxis) <- c(setdiff(class(yaxis), "yaxis1"), "yaxis2")
+    ax$x$ax_opts$yaxis <- NULL
+  }
+  .ax_opt2(ax, "yaxis", l = yaxis)
+}
+
+
+
+
 #' Theme for charts
 #'
 #' @param ax A \code{apexcharts} \code{htmlwidget} object. 

R/utils.R

@@ -58,4 +58,11 @@ formatNoSci <- function(x) {
   return(ax)
 }
 
+# Get parameters from an \code{apexcharts} \code{htmlwidget} object.
+.get_ax_opt <- function(ax, name) {
+  ax$x$ax_opts[[name]]
+}
+
+
+
 

man/ax_yaxis2.Rd

@@ -0,0 +1,33 @@
+% Generated by roxygen2: do not edit by hand
+% Please edit documentation in R/apex-utils.R
+\name{ax_yaxis2}
+\alias{ax_yaxis2}
+\title{Secondary Y-axis options}
+\usage{
+ax_yaxis2(ax, ...)
+}
+\arguments{
+\item{ax}{A \code{apexcharts} \code{htmlwidget} object.}
+
+\item{...}{See arguments from \code{\link{ax_yaxis}}}
+}
+\value{
+A \code{apexcharts} \code{htmlwidget} object.
+}
+\description{
+Secondary Y-axis options
+}
+\examples{
+
+library(dplyr)
+data("economics_long", package = "ggplot2")
+
+eco <- economics_long \%>\% 
+  filter(variable \%in\% c("pce", "pop")) \%>\% 
+  filter(date >= "2000-01-01")
+
+apex(eco, aes(x = date, y = value, color = variable), type = "line") \%>\% 
+  ax_yaxis(title = list(text = "Pce")) \%>\% 
+  ax_yaxis2(opposite = TRUE, title = list(text = "Pop"))
+  
+}