I copied the code for gg.gap to make my own version.
mygg.gap <- function (plot, ylim, segments, tick_width, rel_heights, vjust = 0,
margin = c(top = 1, right = 2, bottom = 1, left = 1), ...)
{
if (!is.list(segments)) {
segments = list(segments)
}
if (all(missing(ylim), is.null(plot$coordinates$limits$y))) {
stop("ylim is undefined")
}
else if (ylim[1] == ylim[2]) {
stop("ylim should not be the same number")
}
else if (missing(ylim)) {
ylim = plot$coordinates$limits$y
}
for (j in 1:length(segments)) {
seg1 = segments[[j]][1]
seg2 = segments[[j]][2]
if (seg1 > seg2) {
if (ylim[1] < ylim[2]) {
msg = paste0("No.", j, " segment: c(",
seg1, ",", seg2, ") is wrong. It should be ",
"c(", seg2, ",", seg1, ")")
stop(msg)
}
}
else if (seg1 < seg2) {
if (ylim[1] > ylim[2]) {
msg = paste0("No.", j, " segment: c(",
seg1, ",", seg2, ") is wrong. It should be ",
"c(", seg2, ",", seg1, ")")
stop(msg)
}
}
else if (seg1 == seg2) {
msg = paste0("No.", j, " segment: c(",
seg1, ",", seg2, ") is wrong. tick_width should not be equal")
stop(msg)
}
}
if (length(segments) >= 2) {
if (ylim[1] < ylim[2]) {
for (k in 2:length(segments)) {
pre.2 = segments[[k - 1]][2]
suf.1 = segments[[k]][1]
if (pre.2 > suf.1) {
pre = paste0("c(", segments[[k - 1]][1],
",", segments[[k - 1]][2], ")")
suf = paste0("c(", segments[[k]][1],
",", segments[[k]][2], ")")
msg = paste0("Segments ", k - 1, " and ",
k, ": ", pre, ",", suf, " are wrong. They should be ",
suf, ",", pre)
stop(msg)
}
}
}
else if (ylim[1] > ylim[2]) {
for (k in 2:length(segments)) {
pre.2 = segments[[k - 1]][2]
suf.1 = segments[[k]][1]
if (pre.2 < suf.1) {
pre = paste0("c(", segments[[k - 1]][1],
",", segments[[k - 1]][2], ")")
suf = paste0("c(", segments[[k]][1],
",", segments[[k]][2], ")")
msg = paste0("Segments ", k - 1, " and ",
k, ": ", pre, ",", suf, " are wrong. They should be ",
suf, ",", pre)
stop(msg)
}
}
}
}
if (ylim[1] < ylim[2]) {
if (min(unlist(segments)) <= ylim[1])
stop("the minimum of segments must be more than the minium of ylim")
if (max(unlist(segments)) > ylim[2])
stop("the maximum of segments must be lower than maximum of ylim")
}
else if (ylim[1] > ylim[2]) {
if (min(unlist(segments)) <= ylim[2])
stop("the minimum of segments must be more than the minium of ylim")
if (max(unlist(segments)) > ylim[1])
stop("the maximum of segments must be lower than maximum of ylim")
}
if (missing(tick_width)) {
tick_width = rep(abs(ylim[2] - ylim[1])/10, (length(segments) +
1))
}
if ((length(tick_width) - length(segments)) < 1) {
int_len = length(tick_width)
for (m in (int_len + 1):(length(segments) + 1)) {
tick_width[m] = tick_width[int_len]
}
}
seg_heights = 0
y_heights = 1
if (length(seg_heights) < length(segments)) {
seg_heights_len = length(seg_heights)
for (m in (seg_heights_len + 1):length(segments)) {
seg_heights[m] = seg_heights[seg_heights_len]
}
}
if (length(y_heights) < (length(segments) + 1)) {
y_heights_len = length(y_heights)
for (m in (y_heights_len + 1):(length(segments) + 1)) {
y_heights[m] = y_heights[y_heights_len]
}
}
if (length(plot$scales$scales) == 0) {
trans = "identity"
}
else if ("trans" %in% names(plot$scales$scales[[1]])) {
trans = plot$scales$scales[[1]]$trans
}
else {
trans = "identity"
}
if ("reverse" %in% trans) {
if (ylim[1] < ylim[2]) {
msg = paste0("ylim: ", "c(", ylim[1],
",", ylim[2], ")", " is wrong. It should be ",
"c(", ylim[2], ",", ylim[1], ")")
stop(msg)
}
}
if ("identity" %in% trans) {
if (ylim[1] > ylim[2]) {
msg = paste0("ylim: ", "c(", ylim[1],
",", ylim[2], ")", " is wrong. It should be ",
"c(", ylim[2], ",", ylim[1], ")")
stop(msg)
}
}
for (i in 1:length(segments)) {
gap = unlist(segments[i])
if (i == 1) {
if (ylim[1] < ylim[2]) {
breaks = seq(ylim[1], gap[1], by = tick_width[i])
}
else if (ylim[1] > ylim[2]) {
breaks = seq(gap[1], ylim[1], by = tick_width[i])
}
p_segment.i <- plot + coord_cartesian(ylim = c(ylim[1],
gap[1])) + theme(panel.border = element_blank()) +
theme(axis.line.y = element_line(), axis.line.x.bottom = element_line(),
plot.title = element_blank(), legend.position = "none") +
scale_y_continuous(expand = c(0, 0), trans = trans,
breaks = breaks) + ylab(label = NULL)
p_segment = list(p_segment.i)
names(p_segment)[length(p_segment)] = i
rel_heigh = c(y_heights[i], seg_heights[i])
}
else {
if (ylim[1] < ylim[2]) {
breaks = seq(ylim[1], gap[1], by = tick_width[i])
}
else if (ylim[1] > ylim[2]) {
breaks = seq(gap[1], ylim[1], by = tick_width[i])
}
p_segment.i <- plot + coord_cartesian(ylim = c(unlist(segments[i -
1])[2], gap[1])) + theme(panel.border = element_blank()) +
theme(axis.line.y = element_line(), legend.position = "none",
axis.text.x = element_blank(), axis.ticks.x = element_blank(),
title = element_blank(), axis.title.x = element_blank()) +
scale_y_continuous(expand = c(0, 0), breaks = breaks,
trans = trans) + ylab(label = NULL)
p_segment = c(p_segment, list(NULL), list(p_segment.i))
names(p_segment)[length(p_segment)] = i
rel_heigh = c(rel_heigh, y_heights[i], seg_heights[i])
}
if (i == length(segments)) {
if (ylim[1] < ylim[2]) {
breaks = seq(gap[2], ylim[2], by = tick_width[i +
1])
}
else if (ylim[1] > ylim[2]) {
breaks = seq(ylim[2], gap[2], by = tick_width[i +
1])
}
p_segment.i <- plot + coord_cartesian(ylim = c(gap[2],
ylim[2])) + theme(panel.border = element_blank()) +
theme(axis.line.y = element_line(), axis.line.x.top = element_line(),
legend.position = "none", axis.text.x = element_blank(),
axis.ticks.x = element_blank(), axis.title.x = element_blank()) +
scale_y_continuous(expand = c(0, 0), breaks = breaks,
trans = trans) + ylab(label = NULL)
p_segment = c(p_segment, list(NULL), list(p_segment.i))
names(p_segment)[length(p_segment)] = i + 1
rel_heigh = c(rel_heigh, y_heights[i])
}
}
num_parts <- length(p_segment)
sbt <- p_segment[[1]]$labels$subtitle
p_segment <- purrr::map(p_segment,
~ if(is.ggplot(.)) {.+labs(subtitle=NULL)} else {NULL})
p_segment = rev(p_segment)
p_segment[[1]]$labels$subtitle <- sbt
if (missing(rel_heights)) {
rel_heights = rev(rel_heigh)
}
else {
rel_heights = rev(rel_heights)
}
if (is.null(plot$theme$axis.title.y$angle)) {
angle = 90
}
else {
angle = plot$theme$axis.title.y$angle
}
plot_grid(plotlist = p_segment, ncol = 1, align = "v",
rel_heights = rel_heights) + theme(plot.margin = unit(margin,
"cm")) + draw_label(label = plot$labels$y, x = 0,
hjust = plot$theme$axis.title.y$hjust, vjust = vjust,
fontfamily = plot$theme$axis.title.y$family, fontface = plot$theme$axis.title.y$face,
size = plot$theme$axis.title.y$size, angle = angle, lineheight = plot$theme$axis.title.y$lineheight,
colour = plot$theme$axis.title.y$colour)
}
Then I used it to run a similar example
data(mtcars)
library(ggplot2)
p<-ggplot(data = mtcars, aes(x = gear, fill = gear)) +
geom_bar() +
labs(title="some title",
subtitle="my subt") +
xlab("Gears")
library(cowplot)
mygg.gap(plot=p,
segments=c(5,10),
ylim=c(0,50))
single subtitle
