Barplot: change x-axis text format

Question

I would like to change the x-axis text format into something like this:

I would like to avoid ggplot and do it with basic 'barplot'

Any suggestion?

Here is my code

df <- data.frame(DK= c("08-01","08-11","08-21","09-01","09-11","09-21","10-01","10-11","10-21","11-01","11-11","11-21","12-01","12-11","12-21","01-01","01-11","01-21","02-01","02-11","02-21","03-01","03-11","03-21","04-01","04-11","04-21","05-01","05-11","05-21","06-01","06-11","06-21","07-01","07-11","07-21"), 
                 value=c(3.9,4.4,5.1,7.1,6.1,7.0,7.8,11.3,13.5,19.6,24.9,27.5,28.0,28.6,41.0,34.3,45.1,43.7,36.0,41.6,27.2,34.3,18.6,24.0,14.0,13.7,12.3,8.5,7.4,6.5,6.2,5.2,5.9,6.3,6.2,7.1))
df

toplot <- df
options(repr.plot.width=6, repr.plot.height=4) 
minv <- min(toplot[,2])-10
maxv <- max(toplot[,2])+10
label <- paste(rep(month.abb[seq(1,12,1)], each = length(c('d1','d2','d3'))), c('d1','d2','d3'))
a <-barplot(toplot$value, 
            names=label, 
            col='deepskyblue3', 
            xaxt = "n", yaxt = "n", 
            ylim=c(0,maxv),
            cex.lab=0.75
) 
axis(1, cex.axis=0.55, las=2, at=a, labels=label) 
axis(2, las='2', cex.axis=0.6)

Does this answer your question? [Multi-row x-axis labels in ggplot line chart](https://stackoverflow.com/questions/20571306/multi-row-x-axis-labels-in-ggplot-line-chart) — Roman, Nov 15 '21 at 14:31
@Roman the OP specifically says that we should have an answer using base R barplot, and avoid ggplot. I don't think it can be closed as a duplicate if the duplicate only has ggplot answers. — Allan Cameron, Nov 15 '21 at 14:57

score 1 · Accepted Answer · answered Nov 15 '21 at 14:53

This gets you fairly close. You need to draw an extra axis for the month labels, and one with no labels but long tick marks to act as the dividers:

toplot <- df
options(repr.plot.width=6, repr.plot.height=4) 
minv <- min(toplot[,2])-10
maxv <- max(toplot[,2])+10
label <- rep(1:3, 12)
a <- barplot(toplot$value, 
             names = label, 
             col = 'deepskyblue3', 
             xaxt = "n", yaxt = "n", 
             ylim = c(0,maxv),
             cex.lab = 0.75
             )

axis(1, cex.axis=0.55, las = 0, at = a, labels = label, tcl = 0,
     padj = -3) 
axis(2, las = 2, cex.axis = 0.6)

axis(1, cex.axis = 1, at = seq(1.8, 41.8, length.out = 12), 
     labels = month.abb, padj = 1, tick = FALSE)
axis(1, at = seq(0, 43.5, length.out = 13), label = FALSE, tcl = -3)

Barplot: change x-axis text format

1 Answers1