问题:

I have the following problem: I would like to visualize a discrete and a continuous variable on a boxplot in which the latter has a few extreme high values. This makes the boxplot meaningless (the points and even the "body" of the chart is too small), that is why I would like to show this on a log10 scale. I am aware that I could leave out the extreme values from the visualization, but I am not intended to.

Let's see a simple example with diamonds data:

The problem is not serious here, but I hope you could imagine why I would like to see the values at a log10 scale. Let's try it:

m + geom_boxplot() + coord_trans(y = "log10")

As you can see the y axis is log10 scaled and looks fine but there is a problem with the x axis, which makes the plot very strange.

The problem do not occur with scale_log, but this is not an option for me, as I cannot use a custom formatter this way. E.g.:

m + geom_boxplot() + scale_y_log10()

My question: does anyone know a solution to plot the boxplot with log10 scale on y axis which labels could be freely formatted with a formatter function like in this thread?

Editing the question to help answerers based on answers and comments:

What I am really after: one log10 transformed axis (y) with not scientific labels. I would like to label it like dollar (formatter=dollar) or any custom format.

If I try @hadley's suggestion I get the following warnings:

> m + geom_boxplot() + scale_y_log10(formatter=dollar) Warning messages: 1: In max(x) : no non-missing arguments to max; returning -Inf 2: In max(x) : no non-missing arguments to max; returning -Inf 3: In max(x) : no non-missing arguments to max; returning -Inf

With an unchanged y axis labels:

回答1:

The simplest is to just give the formatter argument the name of the log function:

m + geom_boxplot() + scale_y_continuous(formatter='log10')

EDIT: Or if you don't like that then either of these appears to give the same result:

EDIT2 & 3: Further experiments (after discarding the one that attempted successfully to put "$" signs in front of logged values):

fmtExpLg10

Note added mid 2017 in comment about package syntax change:

scale_y_continuous(formatter = 'log10') is now scale_y_continuous(trans = 'log10') (ggplot2 v2.2.1)

回答2:

I had a similar problem and this scale worked for me like a charm:

breaks = 10**(1:10) scale_y_log10(breaks = breaks, labels = comma(breaks))

as you want the intermediate levels, too (10^3.5), you need to tweak the formatting:

breaks = 10**(1:10 * 0.5) m

After executing::

回答3:

I think I got it at last by doing some manual transformations with the data before visualization:

And work out a formatter to later compute 'back' the logarithmic data:

formatBack

And draw the plot with given formatter:

Sorry to the community to bother you with a question I could have solved before! The funny part is: I was working hard to make this plot work a month ago but did not succeed. After asking here, I got it.

Anyway, thanks to @DWin for motivation!

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