r - 生成具有交替轴和不同比例的堆叠多面板图

Question

想象一下我们有这样的数据:

    dat <- structure(list(variable = c("a1", "a1", "a1", "a1", "a1", "a1", 
"a2", "a2", "a2", "a2", "a2", "a2", "a3", "a3", "a3", "a3", "a3", 
"a3", "a4", "a4", "a4", "a4", "a4", "a4"), value = c(9.17804065427195, 
-0.477515191225569, 0.189943035684685, -6.06095979017212, -10.4173631972868, 
-6.119330192816, -14.3820530117637, 13.9823789620469, 15.6437973890843, 
0.754856919261315, -0.887052526388938, 7.4096244573169, 0.61043977214679, 
28.4639357142541, 15.4511442682744, 15.8118136384483, 6.65940292893, 
0.467862281678766, 482.791905769932, 493.606761379037, 491.254828253119, 
504.323684433231, 499.323576709646, 492.625278087471)), .Names = c("variable", 
"value"), row.names = c(NA, -24L), class = "data.frame")

我要作图 value对比 value每个 variable ，这样我就有了以下格式的 6 个面板，其中字母代表轴所在的位置和一个 p显示面板所在的位置。

a2   p
a3   p  p
a4   p  p  p  
    a1  a2 a3   

我知道我可以绘制每个并安排数据是否很长......，例如

par(.....)
plot(a1 ~ a2, data=longdat)
plot(a1 ~ a3, data=longdat)
plot(a1 ~ a4, data=longdat)
......

如果这就是我所能做的，那么有一种快速的方法吗？
最好我想知道是否已经有办法做到这一点，比如 facet_wrap或 facet_grid在 ggplot2 Lattice似乎有我想要的那种形状的图(见下文)，但我只能看到如何为 using two axes split per factor 做到这一点.这里的直方图不是必需的，这只是一个例子。



格子可以做类似的事情，但不是我想要的..

xyplot(value~value|variable, 
       data = a, 
       scales=list(alternating=FALSE,relation="same"), 
       layout=c(2,2))

通过重新排序数据，我可以使这项工作正常进行，但是当您更改时 relation至 "free"所以你在轴上为每个变量获得不同的比例，然后将面板分解成单独的面板。

Answer 1

编辑:使用 GGally (v1.0.1)

使用 ggpairs() 更容易来自 GGally 的函数包裹。让 ggpairs()绘制和定位散点图，然后从结果图中删除不需要的元素。首先，以宽格式转换数据。

# Packages
library(GGally)
library(ggplot2)
library(tidyr)

# Data
dat <- structure(list(variable = c("a1", "a1", "a1", "a1", "a1", "a1", 
"a2", "a2", "a2", "a2", "a2", "a2", "a3", "a3", "a3", "a3", "a3", 
"a3", "a4", "a4", "a4", "a4", "a4", "a4"), 
value = c(9.17804065427195, 
-0.477515191225569, 0.189943035684685, -6.06095979017212, -10.4173631972868, 
-6.119330192816, -14.3820530117637, 13.9823789620469, 15.6437973890843, 
0.754856919261315, -0.887052526388938, 7.4096244573169, 0.61043977214679, 
28.4639357142541, 15.4511442682744, 15.8118136384483, 6.65940292893, 
0.467862281678766, 482.791905769932, 493.606761379037, 491.254828253119, 
504.323684433231, 499.323576709646, 492.625278087471)), .Names = c("variable", 
"value"), row.names = c(NA, -24L), class = "data.frame")

# Get the data in its wide format
dat$id <- sequence(rle(as.character(dat$variable))$lengths)
dat2 = spread(data = dat, key = variable, value = value)


# Base plot 
gg = ggpairs(dat2, 
    columns = 2:5,
    lower = list(continuous = "points"),
    diag = list(continuous = "blankDiag"),
    upper = list(continuous = "blank"))

使用来自 here 的代码修剪掉未命名的元素

# Trim off the diagonal spaces
n <- gg$nrow 
gg$nrow <- gg$ncol <- n-1   
v <- 1:n^2
gg$plots <- gg$plots[v > n & v%%n != 0]

# Trim off the last x axis label
# and the first y axis label
gg$xAxisLabels <- gg$xAxisLabels[-n]
gg$yAxisLabels <- gg$yAxisLabels[-1]

# Draw the plot
gg = gg + 
     theme_bw() + 
     theme(panel.grid = element_blank())
gg

原装
pairs()函数让您接近，但如果您只需要布局矩阵中显示的六个面板，那么您可能必须手动构建它。您可以使用 grid 构建图表, 或 ggplot和 gtable .这是一个 ggplot / gtable版本。

该脚本适用于您的 dat数据文件(即长格式)。它构造了六个 ggplot 的列表散点图。 ggplots 转换为 grobs，并提取相关轴 - 将成为新图表中左侧和底部轴的轴。构建了 gtable 布局，并将散点图 grobs(仅限绘图面板)添加到布局中。修改布局以采用轴，然后再次修改布局以采用可变标签。最后，还有一点整理。

dat <- structure(list(variable = c("a1", "a1", "a1", "a1", "a1", "a1", 
"a2", "a2", "a2", "a2", "a2", "a2", "a3", "a3", "a3", "a3", "a3", 
"a3", "a4", "a4", "a4", "a4", "a4", "a4"), 
value = c(9.17804065427195, 
-0.477515191225569, 0.189943035684685, -6.06095979017212, -10.4173631972868, 
-6.119330192816, -14.3820530117637, 13.9823789620469, 15.6437973890843, 
0.754856919261315, -0.887052526388938, 7.4096244573169, 0.61043977214679, 
28.4639357142541, 15.4511442682744, 15.8118136384483, 6.65940292893, 
0.467862281678766, 482.791905769932, 493.606761379037, 491.254828253119, 
504.323684433231, 499.323576709646, 492.625278087471)), .Names = c("variable", 
"value"), row.names = c(NA, -24L), class = "data.frame")

# Load packages
library("ggplot2")
library("plyr")
library("gtable")
library(grid)

# Number of items and item labels
item = unique(dat$variable)
n = length(item)

## List of scatterplots
scatter <- list()

for (i in 1:(n-1)) {
   for (j in (i+1):n) {

# Data frame 
df.point <- na.omit(data.frame(cbind(x = dat[dat$variable == item[i], 2], y = dat[dat$variable == item[j], 2])))

# Plot
p <- ggplot(df.point, aes(x, y)) +
   geom_point(size = 1) +
   theme_bw() + 
   theme(panel.grid = element_blank(),
          axis.text = element_text(size = 6))

name <- paste0("Item", i, j)
scatter[[name]] <- p
} }

# Convert ggplots to grobs
scatterGrob <- llply(scatter, ggplotGrob)

# Extract the axes as grobs
# x axis
xaxes = subset(scatterGrob, grepl(paste0("^Item.", n), names(scatterGrob))) 
xaxes = llply(xaxes, gtable_filter, "axis-b")

# y axis
yaxes = subset(scatterGrob, grepl("^Item1.*", names(scatterGrob))) 
yaxes = llply(yaxes, gtable_filter, "axis-l")

# Tick marks and tick mark labels are easier to position if they are separated. 
labelsb = list(); ticksb = list(); labelsl = list(); ticksl = list()
for(i in 1:(n-1)) {
  x = xaxes[[i]][[1]][[1]]$children[[2]]
  labelsb[[i]] = x$grobs[[2]]
  ticksb[[i]] = x$grobs[[1]]

  y = yaxes[[i]][[1]][[1]]$children[[2]]
  labelsl[[i]] = y$grobs[[1]]
  ticksl[[i]] = y$grobs[[2]]
} 

## Extract the plot panels
scatterGrob <- llply(scatterGrob, gtable_filter, "panel")

## Set up initial gtable layout
gt <- gtable(unit(rep(1, n-1), "null"), unit(rep(1, n-1), "null"))

# Add scatterplots in the lower half of the matrix
 k <- 1
 for (i in 1:(n-1)) {
    for (j in i:(n-1)) {
 gt <- gtable_add_grob(gt, scatterGrob[[k]], t=j, l=i)
 k <- k+1
 } }

# Add rows and columns for axes
gt <- gtable_add_cols(gt, unit(0.25, "lines"), 0)
gt <- gtable_add_cols(gt, unit(1, "lines"), 0)
gt <- gtable_add_rows(gt, unit(0.25, "lines"), 2*(n-1))
gt <- gtable_add_rows(gt, unit(0.5, "lines"), 2*(n-1))

for (i in 1:(n-1)) {
  gt <- gtable_add_grob(gt, ticksb[[i]], t=(n-1)+1, l=i+2)
  gt <- gtable_add_grob(gt, labelsb[[i]], t=(n-1)+2, l=i+2)
  gt <- gtable_add_grob(gt, ticksl[[i]], t=i, l=2)
  gt <- gtable_add_grob(gt, labelsl[[i]], t=i, l=1)
}

# Add rows and columns for variable names
gt <- gtable_add_cols(gt, unit(1, "lines"), 0)
gt <- gtable_add_rows(gt, unit(1, "lines"), n+1)
for(i in 1:(n-1))  gt <- gtable_add_grob(gt, 
           textGrob(item[i], gp = gpar(fontsize = 8)), t=n+2, l=i+3)
for(i in 2:n)  gt <- gtable_add_grob(gt, 
           textGrob(item[i], rot = 90, gp = gpar(fontsize = 8)), t=i-1, l=1)

# Add small gaps between the panels
for(i in (n-1):2) {
  gt <- gtable_add_cols(gt, unit(0.4, "lines"), i+2)
  gt <- gtable_add_rows(gt, unit(0.4, "lines"), i-1)
}

# Add margins to the whole plot
for(i in c(2*(n-1)+2, 0)) {
    gt <- gtable_add_cols(gt, unit(.75, "lines"), i)
    gt <- gtable_add_rows(gt, unit(.75, "lines"), i)
}

# Turn clipping off
gt$layout$clip = "off"

# Draw it
grid.newpage()
grid.draw(gt)