search for: 7echen_1002

Hi there, I am looking for a function that takes a vector as input and generates all pair wise combination of the elements of the input vector. For example, the input vector is c(1,2,3,4). The output vector is c(1 and 2, 1 and 3, 1 and 4, 2 and 3, 2 and 4, 3 and 4). The representation here is generic. I can use a for loop to do it, but it gets slow when the number of elements of the input