Explore Courses Blog Tutorials Interview Questions
0 votes
in R Programming by (5.3k points)

I have a data frame with several columns; some numeric and some character. How to compute the sum of a specific column? I’ve googled for this and I see numerous functions (sum, cumsum, rowsum, rowSums, colSums, aggregate, apply) but I can’t make sense of it all.

For example, suppose I have a data frame people with the following columns

Name Height Weight

Mary 65     110

John 70     200

Jane 64     115

How do I get the sum of all the weights?

1 Answer

0 votes

To sum all values in a column of a data frame, you can use the sum() function from the base package as follows:

sum(people$Weight, na.rm = TRUE) 

#na.rm = TRUE will remove all 'NA' values in the column

For example:

df <- data.frame(p=c(10,8,7,3,2,6,7,8),


> df

   p   v

1 10 100

2  8 300

3  7 150

4  3 400

5  2 450

6  6 250

7  7 150

8  8 400

sum(df$p, na.rm = TRUE)

[1] 51

Note - you can get built-in help by using ?sum, ?colSums, etc. (by the way, colSums will give you the sum for each column).

Welcome to Intellipaat Community. Get your technical queries answered by top developers!

29.3k questions

30.6k answers


104k users

Browse Categories