R 如何控制条形图中值标签的小数位数

考虑下图：

这个问题是关于如何将堆叠条中的所有值标签保留在小数点后一位，以保持一致性。因此，将-1、2和5表示为-1.0、2.0和5.0，与其他表示一致。下面是一个示例数据

df  <- data.frame(group=c("satisfied", "satisfied",
                      "unsatisfied","unsatisfied",
                      "satisfied", "satisfied", 
                      "unsatisfied","unsatisfied"
                      ), 
                cost=c("low","high","low","high",
                      "low","high","low","high"),     
                treatment=c("treated","treated","treated","treated",
                            "untreated","untreated",
                      "untreated","untreated") ,
                value=c(2.3,8.7,5.0,3.1,9.4,3.1,2.0,-1.0)) 

---

进入ggplot函数，但这不会产生所需的输出。我非常感谢您在这方面提供的帮助。

问题是您在使用

sprintf

之前进行了四舍五入（并因此转换为

字符

，丢失了数字信息）。要格式化数字，您需要给出

sprintf

数字，而不是字符串。它将自行处理舍入问题。试试这个：

label = ifelse(value !=0, sprintf("%0.1f", value), "")

制定整个代码：

ggplot(data = df, aes(y = value, x = group, fill = cost)) +
  geom_bar(stat = "identity", position = 'stack') +
  ylab("Y label") +
  theme(
    legend.direction = "horizontal",
    legend.position = "bottom",
    legend.spacing.x = unit(0.1, 'cm')
  ) +
  theme(legend.title = element_blank()) +
  geom_text(aes(label = ifelse(value !=0, sprintf("%0.1f", value), "")),
            position = position_stack(vjust = 0.5)) +
  facet_grid(~ treatment)

---

由于

ifelse

，上面的内容有点奇怪。一个更标准的

ggplot2

解决方案会让您以另一种方式摆脱0-可能在打印前过滤掉它，将

data=filter（df，y！=0）

赋予

ggplot（）

。然后您可以使用

缩放

功能

label = scales::label_number(accuracy = 0.1)(value)

将整个代码制作如下，以获得相同的结果：

ggplot(data = dplyr::filter(df, value != 0), aes(y = value, x = group, fill = cost)) +
  geom_bar(stat = "identity", position = 'stack') +
  ylab("Y label") +
  theme(
    legend.direction = "horizontal",
    legend.position = "bottom",
    legend.spacing.x = unit(0.1, 'cm')
  ) +
  theme(legend.title = element_blank()) +
  geom_text(aes(label = scales::label_number(accuracy = 0.1)(value)),
            position = position_stack(vjust = 0.5)) +
  facet_grid(~ treatment)

---

真正地使用示例数据尝试新的R会话。这对我来说很好。

label = scales::label_number(accuracy = 0.1)(value)

ggplot(data = dplyr::filter(df, value != 0), aes(y = value, x = group, fill = cost)) +
  geom_bar(stat = "identity", position = 'stack') +
  ylab("Y label") +
  theme(
    legend.direction = "horizontal",
    legend.position = "bottom",
    legend.spacing.x = unit(0.1, 'cm')
  ) +
  theme(legend.title = element_blank()) +
  geom_text(aes(label = scales::label_number(accuracy = 0.1)(value)),
            position = position_stack(vjust = 0.5)) +
  facet_grid(~ treatment)