boxplot of vectors with different length

Question

I have a matrix of 2 columns. I would like boxplot each of these columns but each has different number of entries.

For example, first column has 10 entries and the second column has 7 entries. The remaining 3 of the second column is given zero.

I would like to plot these side by side for comparison reasons.

Is there a way to tell R to boxplot the whole column 1 and only the first 7 entry for column 2?

Answer 1

You could simply index the values you want, for example

## dummy version of your data
mat <- matrix(c(1:17, rep(0, 3)), ncol = 2)

## create object suitable for plotting with boxplot
## I.e. convert to melted or long format
df <- data.frame(values = mat[1:17],
                 vars = rep(c("Col1","Col2"), times = c(10,7)))

## draw the boxplot
boxplot(values ~ vars, data = df)

In the above I'm taking you at your word that you have a matrix. If you actually have a data frame then you would need

df <- data.frame(values = c(mat[,1], mat[1:7, 2]),
                 vars = rep(c("Col1","Col2"), times = c(10,7)))

and I assume that the data in the two columns are comparable in that the fact that the values are in two columns suggests a categorical variable that allows us to split the values (like Height of men and women, with sex as the categorical value).

The resulting boxplot is shown below