[R] Extracting only the non-repeated rows of matrices

I have 2 matrices. One which contains a complete set of row combinations. Another which contains a subset of the first. What I would like to extract is the rows which are in the first but not repeated in the second. For instance if the following were my two matrices, A [,1] [,2] [,3] [,4]

[R] matching rows in matrices

I have a matrix such as this, [,1] [,2] [,3] [1,]112 [2,]255 and a larger matrix such as this, a b [1,] 1 5 [2,] 2 5 [3,] 4 9 [4,] 5 8 [5,] 7 8 [6,] 7 10 [7,] 9 10 what I want to do is check the number of times the columns in the first matrix appear as r

[R] Deleting repeated rows

Appologies if this is a simple problem. I have a matrix which is 86x3 and each row contains three integers. The problem I have is that some of the rows of integers are repeated in other rows and I only wish to have one copy of these rows. Is there a function that I can use which will identify the