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rtidyverserow

Sum two rows with numeric values

In this picture, I want to add the values of the two "Rural municipality" to make them one. I don't seem to know how to do this.

table

Solution

  • It is also possible with base R. One possible approach is to set the discriminating string of rows to be added to the same value and aggregate by this string.

    Example with a builtin dataset:

    > s <- apply(Titanic, c("Class","Survived"), sum)
> x <- data.frame(Class=rownames(s), No=s[,"No"], Yes=s[,"Yes"])
> x$Class <- as.character(x$Class)
> x
     Class  No Yes
1st    1st 122 203
2nd    2nd 167 118
3rd    3rd 528 178
Crew  Crew 673 212

    To combine (sum) the two rows of 1st and 2nd class, we first assign them a new identical Class name, and then aggregate by Class:

    > x[x$Class %in% c("1st","2nd"), "Class"] <- "upper"
> aggregate(. ~ Class, data=x, FUN=sum)
  Class  No Yes
1   3rd 528 178
2  Crew 673 212
3 upper 289 321