How to make generic the formula parameter of naiveBayes() in R?

When I'm using the function naiveBayes() of the library "e1071" it is required to insert a formula of the type:

myFormula <- myClass~ feature1 + feature2 + feature3

If I want to make it generic (I don't know how many features has the relative dataset) how can I do? I just know the myClass column will be the last one, and I want to keep in considerations all other columns

Solution

You can refer to all other columns dynamically with the ..

myFormula <- cyl ~ .
naiveBayes(myFormula, data = mtcars)



    Call:
naiveBayes.default(x = X, y = Y, laplace = laplace)

A-priori probabilities:
Y
      4       6       8 
0.34375 0.21875 0.43750 

Conditional probabilities:
   mpg
Y       [,1]     [,2]
  4 26.66364 4.509828
  6 19.74286 1.453567
  8 15.10000 2.560048

   disp
Y       [,1]     [,2]
  4 105.1364 26.87159
  6 183.3143 41.56246
  8 353.1000 67.77132

If you want the class dymanic, you can use substitute the formula and use eval to evaluate it inside the naiveBayes function call.

dynamicNB <- function(data, class) {
  myFormula <- substitute(class ~ .)
  naiveBayes(eval(myFormula), data = data)
}

dynamicNB(class = mpg, data = mtcars)