[R] Counting zeros in a matrix

[Richard M. Heiberger]

A <- matrix(c(
1,1,1,1,0,1,1,1,1,
1,1,1,0,1,0,1,0,0,
1,0,1,0,0,1,0,0,0,
1,1,0,0,0,0,1,0,0),
4, 9, byrow=TRUE)

apply(A, 1, function(x) sum(diff(x)==1))