Sum by Group in R (2 Examples) | Apply aggregate Function to Vector / Column / Variable

R code of this tutorial:

data(iris) # Load iris data
head(iris) # First six rows

aggregate(x = iris$Sepal.Length, # Specify data column
by = list(iris$Species), # Specify group indicator
FUN = sum) # Specify function (i.e. sum)

[simonstoffels]

Exactly what i was looking for. Thanks fir your amazing work this would have cost me days

[jaikishank]

thanks and it was a very good explanation

[preetidhiman]

Can we apply aggregate function to add two columns based on one list. If yes, plz enlighten me with the code.

[tsunetasora]

0:28 You don't need to double click, just click once to open a dataframe.

[robb]

The function is working for me. In a big data set it shows lot of groups, is there any way we can filter particular group?

[josephravi]

the video is helpful to perform the aggregate function for one variable. could you please specify the command for the sum of items from multiple columns( eg I have to compute the sum of items from VAR 6 from particular raw of Var 1 and then particular rows from Var 2. and then by Particular rows of VAR 5

[carlestr]

Hi, thanks for your video. I have one question. How can I have the sum of all the variables depending on the species?

[Janith]

How do you use the 'max' (maximum value) for the function. It gives an error.