Mean of a column in a data frame, given the column's name

Question

I\'m inside a big function I have to write. In the last part I have to calculate the mean of a column in a data frame. The name of the column I am operating on is given as a

Answer 1

if your column contain any value that you want to neglect. it will help you

## da is data frame & Ozone is column name 

##for single column
mean(da$Ozone, na.rm = TRUE)  

##for all columns
colMeans(x=da, na.rm = TRUE)