This is my first post, so sorry if I do anything wrong

I have the same problem mentioned here:

https://community.rstudio.com/t/how-to-sum-columns-to-create-a-new-row-of-data-in-a-dataframe/96673, but when I try to apply the solution I get an error: Error in colSums (dat1): 'x' must be numeric.

I assume that this is because one of the columns has character format, but I don't know how to include it in the proposed solution: dat1 [nrow (dat1) + 1,] <- colSums (dat1).

Any idea? Thanks to all in advance.