我正在尝试使用ggplot2和gridExtra包为两个聚类条形图添加图例。两个图表都有相同的图例，即时间（帖子前）。
我可以得到两个相同大小的图形彼此相邻，但是如果我只是在右图上省略legend.position = "none"参数，则包含图例但它会收缩图形。任何人都可以建议在右图的右侧包含图例的方法吗？
第一个图表的单元格和列名称如下
Graph 1
Time GroupDC1C0 CWSQTot
1 Pre High Expectancy 43.54545
2 Post High Expectancy 28.81818
3 Pre Low Expectancy 43.31111
4 Post Low Expectancy 36.55556
Graph 2
Time GroupDC1C0 CWSQCrav
1 Pre High Expectancy 4.977273
2 Post High Expectancy 1.659091
3 Pre Low Expectancy 4.955556
4 Post Low Expectancy 3.688889
ggplot2中两个图的代码如下
require(ggplot2)
clusteredBarsTot <- ggplot(cellMeansTot, aes(GroupDC1C0,CWSQTot)) +
geom_bar(aes(fill = Time), stat = "identity", position = "dodge", size = .5) +
scale_fill_manual(values = c("#999999", "#666666")) +
expand_limits(y = 50) +
xlab("") + ylab("CWSQ Score") +
theme_bw()
clusteredBarsCrav <- ggplot(cellMeansCrav, aes(GroupDC1C0,CWSQCrav)) +
geom_bar(aes(fill = Time), stat = "identity", position = "dodge", size = .5) +
scale_fill_manual(values = c("#999999", "#666666")) +
expand_limits(y = 6) +
xlab("") + ylab("CWSQ Craving Score") +
theme_bw()
titleFont <- element_text(face = "bold", color = "black", size = 16, vjust = 1.5)
titleFontX <- element_text(face = "bold", color = "black", size = 16, vjust = 0.01)
axisTextFont <- element_text(face = "plain", color = "black", size = 13) # y-axis numbers size
axisTextFontX <- element_text(face = "plain", color = "black", size = 11, angle = 45, hjust = 1, vjust = 1) #x-axis day labels
legendTitle <- element_text(face = "bold", color = "black", size = 14)
legendText <- element_text(face = "plain", color = "black", size = 13)
# add fix-ups to graph (fonts, angles on axis labels etc.) via theme argument
clusBarTot <- clusteredBarsTot + theme(title = titleFont,
axis.title = titleFont,
axis.title.x = titleFontX,
axis.text = axisTextFont,
axis.text.x = axisTextFontX,
legend.position = "none",
panel.grid.minor = element_blank(),
panel.grid.major = element_blank())
clusBarCrav <- clusteredBarsCrav + theme(title = titleFont,
axis.title = titleFont,
axis.title.x = titleFontX,
axis.text = axisTextFont,
axis.text.x = axisTextFontX,
legend.position = "none",
panel.grid.minor = element_blank(),
panel.grid.major = element_blank())
require(gridExtra)
#####side by side bar graphs
grid.arrange(clusBarTot, clusBarCrav, ncol=2)
##### draw lines on Totals graph
grid.lines(c(0.205, 0.365), c(0.87, 0.87))
grid.lines(c(0.205, 0.205), c(0.87, 0.855))
grid.lines(c(0.365, 0.365), c(0.87, 0.855))
####### draws a label on the Total graph
grid.text(expression(italic(p)==".006"),
x= unit(0.29, "npc"), y = unit(0.9, "npc"),
gp=gpar(fontsize = 11))
##### draw lines on Craving graph
grid.lines(c(0.695, 0.861), c(0.845, 0.845))
grid.lines(c(0.695, 0.695), c(0.845, 0.83))
grid.lines(c(0.861, 0.861), c(0.845, 0.83))
####### draws a label on the Craving graph
grid.text(expression(italic(p)~"< .001"), x= unit(0.785, "npc"), y = unit(0.875, "npc"),
gp=gpar(fontsize = 11))
我在stackexchange上看到一个帖子，该帖子编写了一个用常规图例布置图表的方法代码。但是，这些图形显示在一列中，图例位于单独的列中。我试着玩这个代码并在函数中输入我的两个图，但是我不太了解R以便像这样反向工程代码。代码如下：
grid_arrange_shared_legend <- function(...) {
plots <- list(...)
g <- ggplotGrob(plots[[1]] + theme(legend.position="bottom"))$grobs
legend <- g[[which(sapply(g, function(x) x$name) == "guide-box")]]
lheight <- sum(legend$height)
grid.arrange(
do.call(arrangeGrob, lapply(plots, function(x)
x + theme(legend.position="none"))),
legend,
ncol = 2,
heights = unit.c(unit(1, "npc") - lheight, lheight))
}
grid_arrange_shared_legend(clusBarTot, clusBarCrav)
正如你在代码中我的naff评论所说，我对R和编程仍然很陌生。
答案 0 :(得分：0)
你正确地使用这个。如果要将图例的位置从底部（正如您所引用的问题中所请求的）更改为右侧，则以您说图例位置应该正确的方式更改代码（第三行代码并且您希望有3列，新代码应如下所示：
grid_arrange_shared_legend <- function(...) {
plots <- list(...)
g <- ggplotGrob(plots[[1]] + theme(legend.position="right"))$grobs
legend <- g[[which(sapply(g, function(x) x$name) == "guide-box")]]
lheight <- sum(legend$height)
grid.arrange(
do.call(arrangeGrob, lapply(plots, function(x)
x + theme(legend.position="none"))),
legend,
ncol = 3,
heights = unit.c(unit(1, "npc") - lheight, lheight))
}
grid_arrange_shared_legend(clusBarTot, clusBarCrav)