在R中绘制大小不同的独立数据集

Question

I want to read 3 independent data sets each of which having a different size and plot them using a boxplot, eg:

Set1 Set2 Set3
1    1    1
1    2    2
1    2    2
     3    3
     3    3
          4

(As string: "Set1 Set2 Set3\\n1 1 1\\n1 2 2\\n1 2 2\\n 3 3\\n 3 3\\n 4\\n" )

However, the column width could vary, eg when a value has more than 5 digits.

When I do results = read.table("data.dat", header=TRUE) RStudio will report:

line 4 did not have 3 elements

Using the option fill=TRUE would shift every field in line 4 to the left and fill the empty field ont the right with a NA which directly biases the data.

Because of the fact that the column size may vary, I tried to load it as a CSV file but this had the effect that the median for Set1 became NA .

Same data as CSV:

Set1,Set2,Set3
1,1,1
1,2,2
1,2,2
,3,3
,3,3
,,4

So how can I plot all sets in a single diagram without the data being changed by R?

EDIT1: Gave more details for the used data format. Also I emphasize that the column size might vary and not be as fixed in the example

Answer 1

This reads the indicated file with the indicated field widths. The first (header line) is skipped and the indicated column names are used. Empty fields ( na.strings="" ) are regarded as NA :

results <- read.fwf("data.dat", widths = c(5L, 5L, 5L), skip = 1, 
  na.strings = "", col.names = c("Set1", "Set2", "Set3"))

boxplot(results)

(continued after image)

Note: One cannot tell the exact content of data.dat from the question and that could be crucial but for purposes of this answer we have assumed this:

Lines <- c("Set1 Set2 Set3", 
           "1    1    1", 
           "1    2    2", 
           "1    2    2", 
           "     3    3", 
           "     3    3", 
           "          4")
writeLines(Lines, "data.dat")