如何使用 R plotly 在条形图中的条形末端（而不是居中）放置刻度线和轴标签（或刻度文本）？

Question

I am trying to create a bar chart that shows how much funds received households of certain income. For that I am using the following code:

chart <- plot_ly(funds,
                  x = ~income_group, 
                  y = ~FundsSent, 
                  type = "bar")

chart <- chart %>% layout(title = '<b>Fund Distribution by Income</b>',
                            xaxis = list(
                              title = list(text='Income', standoff = 10), 
                              ticks="outside", tickson="boundaries"),
                            yaxis = list(
                              title = list(text='Funds paid', standoff = 10)),
                            bargap = 0.05)

Now, with "tickson=boundaries" I managed to get the tickmarks at the end of every bar (rather than centered), but the labels are still in the middle of the column.

Bar chart showing missplacement of axis labels

This tells the wrong story, as it would appear that the first column for example shows the funds paid to those with 0 income, when instead it's showing the funds paid to those with income 0 to 5,000.

I have also tried setting the X axis labels by hand, using tickmode="array" , ticktext and setting tickvals manually but, while that aligns the ticks with the text, it goes again to centering the tickmarks (as if the tickson="boundaries" argument wasn't working anymore).

Any help for a desperate and frustrated economist?

Answer 1

I actually just made it work using tickson="boundaries" to set the ticks in between bars; setting tickvals to half of the interval range to the left to move the ticks off the center, and ticktext for the labels.

The reason it wasn't working before is because I had written my tickvals without using "" (I thought that, being numbers rather than text, I didn't need the inverted commas). This is how my code looks now, and it works:

chart %>% layout(title = '<b>Fund Distribution by Income</b>',
                 xaxis = list(
                   title = list(text='<b>Income</b>', standoff = 10),
                   ticks="outside", tickson="boundaries",
                   ticktext=list("0", "5,000", "10,000", "15,000", "20,000"), #label
                   tickvals=list("-2500", "2500", "7500", "12500", "17500")) #position