Automating function evaluation - R

Question

"Data" refers to an 100 by 3 matrix. "FUNCTION" is a function of the three variables, which correspond to the columns of Data. I would like to evaluate FUNCTION using the elements of each row of Data; eg,

FUNCTION(Data[1, "Age"], Data[1, "Height"], Data[1, "Obs_FVC"])

Is there a way to evaluate FUNCTION at each row automatically?

Answer 1

The short answer is: use apply

result <- apply(Data, 1, function(x) {
    FUNCTION(x[['Age']], x[['Height']], x[['Obs_FVC']])
})

The second argument determines if apply operates on your matrix in a row-wise (1) or column-wise (2) fashion.You can even do both ( c(1, 2) )!