发散条图.qmd

# 发散条图

Diverging Bars

## geom_linerange

```{r}
library(data.table)
df <- datasets::mtcars %>% data.table() %>% .[,cars:=rownames(mtcars)]

df[,mpg_z:=scale(mpg)]
df[mpg_z>0,mpg_c:="g"]
df[mpg_z<0,mpg_c:="r"]
```

```{r}
ggplot(df,aes(y=reorder(cars,mpg_z),colour = mpg_c))+
    geom_linerange(aes(xmin = 0,
                       xmax = mpg_z),
                   linewidth=2,alpha=.5,show.legend = F)+
    scale_color_manual(values = c("r"="red","g"="green"))+
    scale_x_continuous(limits = c(-2,2.5),breaks = seq(-2,2.5,0.5),expand = c(0,0.02))+
    scale_y_discrete(expand = c(0.03,0.03))+
    labs(x="Mileage",y="Model",title = "Diverging Bars of Car Mileage")+
    theme_bw()+
    theme(
        aspect.ratio = 1/1.3,
        axis.ticks = element_blank(),
        axis.title = element_text(face = "italic"),
        axis.text.y = element_text(size = 8),
        panel.grid.minor = element_blank(),
        plot.title = element_text(hjust = .5)
    )+
    geom_text(
        data = df[mpg_c=="g"],
        mapping = aes(x=mpg_z,label = sprintf("%.2f",mpg_z)),hjust = 0,colour = "green4",size = 2
    )+
    geom_text(
        data = df[mpg_c=="r"],
        mapping = aes(x=mpg_z,label = sprintf("%.2f",mpg_z)),hjust = 1,colour = "red4",size = 2
    )
```

## geom_segment

```{r}
ggplot(df)+
    geom_segment(aes(x = 0,xend = mpg_z,
                     y=reorder(cars,mpg_z),yend =reorder(cars,mpg_z),
                     colour=mpg_c),
                   linewidth=2,alpha=.5,show.legend = F)+
    scale_color_manual(values = c("r"="red","g"="green"))+
    scale_x_continuous(limits = c(-2,2.5),breaks = seq(-2,2.5,0.5),expand = c(0,0.02))+
    scale_y_discrete(expand = c(0.03,0.03))+
    labs(x="Mileage",y="Model",title = "Diverging Bars of Car Mileage")+
    theme_bw()+
    theme(
        aspect.ratio = 1/1.3,
        axis.ticks = element_blank(),
        axis.title = element_text(face = "italic"),
        axis.text.y = element_text(size = 8),
        panel.grid.minor = element_blank(),
        plot.title = element_text(hjust = .5)
    )
```

## geom_bar

```{r}
ggplot(df,aes(x=reorder(cars,mpg_z),y=mpg_z,fill = mpg_c))+
    geom_bar(stat = "identity",
                   width=0.5,alpha=.5,show.legend = F)+
    scale_fill_manual(values = c("r"="red","g"="green"))+
    scale_y_continuous(limits = c(-2,2.5),breaks = seq(-2,2.5,0.5),expand = c(0,0.02))+
    scale_x_discrete(expand = c(0.03,0.03))+
    labs(x="Mileage",y="Model",title = "Diverging Bars of Car Mileage")+
    theme_bw()+
    theme(
        aspect.ratio = 1/1.3,
        axis.ticks = element_blank(),
        axis.title = element_text(face = "italic"),
        axis.text.y = element_text(size = 8),
        panel.grid.minor = element_blank(),
        plot.title = element_text(hjust = .5)
    )+
    coord_flip()
```