How to sum value of a column based on equality from another column and create a new dataframe

Question

this is my first question on stackoverflow. I hope to describe precisely enough my problem. So I'm trying to sum the value of a column called 'Fraction' based on equality of another column called 'Seq'. My dataframe looks like:

Fraction	Seq
0.0872	CASSFAVQGGETQYF
0.0105	CASSFAVQGGETQYF

The hopeful output matrix should looks like

Fraction	Seq
0.0977	CASSFAVQGGETQYF

I would like a new dataframe to be created from this operation. I have tried to use ddply but nothing successful resulted from it. Thank you for your help.

Answer 1

You can achieve this in base R using aggregate

aggregate(Fraction ~ Seq, FUN = "sum", data = df)

Or in dplyr using group_by and summmarise

df %>% 
group_by(Seq) %>% 
summarize(Fraction = sum(Fraction))