search for: posile

...uot;, ...) boxplot(data2 ~ month, add=T, col = "blue", ...) The problem is that the data from February are missing for data2, so R think that must take little more space between the data classes in data 2 and then both data gropus are not aligned. In the R documentation I do not find any posile solution for tell R that I want reserve a extra space for this month, So the boxplot is erroneous and the x axis have a strange numeration 1 2 3 4 54 65 76 ... etc I would be grateful if anyone could suggest how to tell R That the boxplots must be fitted to the same x class in both data groups....