Add second axes (top and right) with minor ticks-CodePudding

I am trying to create a plot that has an axis on the top and the right side of the plot. I added minor ticks to the x and y-axis but I noticed that when I try and add a second x and y-axis, the minor ticks are removed. I was also hoping to remove the second axis labels but that doesn't seem to work. I am wondering if there is an issue with how I added the minor ticks?

Do my main questions are, how can I add minor ticks to the second axes and how can I remove the labels.

data.bw <- structure(list(num = c(88L, 58L, 15L, 11L, 14L, 29L, 34L, 40L, 
24L, 20L, 3L, 1L, 1L), bar = c(0.5, 1.5, 2.5, 3.5, 4.5, 5.5, 
6.5, 7.5, 8.5, 9.5, 10.5, 11.5, 12.5), group = structure(c(1L, 
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L), .Label = "A", class = "factor")), class = "data.frame", row.names = c(NA, 
-13L))

library(ggplot2)
library(ggh4x)

    ggplot(data.bw, aes(bar,num, fill = group))  
      geom_bar(stat = 'identity', width = 1)   
      scale_fill_manual(values = c('orange', 'khaki'))   
      scale_y_continuous(
        minor_breaks = seq(0, 90, by = 2),
        breaks = seq(0, 90, by = 10), limits = c(0, 90),
        expand = expansion(mult = c(0, 0)),
        sec.axis = dup_axis(name = NULL),
        guide = "axis_minor" 
      )  
      scale_x_continuous(
        minor_breaks = seq(0, 14, by = 0.5),
        breaks = seq(0, 14, by = 2), limits = c(0, 14),
        expand = expansion(mult = c(0, 0)),
        sec.axis = dup_axis(name = NULL),
        guide = "axis_minor"
      )  
      scale_fill_manual(values = alpha(c("red"), .3))  
      theme_bw()  
      theme(
        panel.border = element_rect(colour = "black", fill=NA, size=1),
        plot.background = element_blank(),
        panel.grid.major = element_blank(),
        panel.grid.minor = element_blank()
      )

CodePudding user response：

As far as I know, secondary axes in ggplot2 don't get any minor break information to pass on to the guides (or get bungled up). See also related issue. However, since you're using dup_axis(), I'm presuming you want to duplicate your primary axes, which you can also do with guides(x.sec = "axis_minor", y.sec = "axis_minor"), which take their order directly from the scale instead of a secondary scale.

Removing the labels of the secondary axes is as simple as setting the appropriate theme elements to element_blank(). Had you meant the axis titles instead of text, these are off by default but you can pass them as guides(x.sec = guide_axis_minor(title = "My title")) had you wanted them.

data.bw <- structure(list(num = c(88L, 58L, 15L, 11L, 14L, 29L, 34L, 40L, 
                                  24L, 20L, 3L, 1L, 1L), bar = c(0.5, 1.5, 2.5, 3.5, 4.5, 5.5, 
                                                                 6.5, 7.5, 8.5, 9.5, 10.5, 11.5, 12.5), group = structure(c(1L, 
                                                                                                                            1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L), .Label = "A", class = "factor")), class = "data.frame", row.names = c(NA, 
                                                                                                                                                                                                                                                   -13L))

library(ggplot2)
library(ggh4x)

ggplot(data.bw, aes(bar,num, fill = group))  
  geom_bar(stat = 'identity', width = 1)   
  scale_fill_manual(values = c('orange', 'khaki'))   
  scale_y_continuous(
    minor_breaks = seq(0, 90, by = 2),
    breaks = seq(0, 90, by = 10), limits = c(0, 90),
    expand = expansion(mult = c(0, 0)),
    guide = "axis_minor" 
  )  
  scale_x_continuous(
    minor_breaks = seq(0, 14, by = 0.5),
    breaks = seq(0, 14, by = 2), limits = c(0, 14),
    expand = expansion(mult = c(0, 0)),
    guide = "axis_minor"
  )  
  guides(x.sec = "axis_minor", y.sec = "axis_minor")  
  theme_bw()  
  theme(
    panel.border = element_rect(colour = "black", fill=NA, size=1),
    plot.background = element_blank(),
    panel.grid.major = element_blank(),
    panel.grid.minor = element_blank(),
    axis.text.x.top = element_blank(),
    axis.text.y.right = element_blank()
  )

^{Created on 2021-09-13 by the reprex package (v2.0.1)}