1.4
> x <- 11 > x [1] 11 > x1 <- c(1,3,5,7,9) > x1 [1] 1 3 5 7 9 > gender <- c("male", "female") > gender [1] "male" "female" > 2:7 [1] 2 3 4 5 6 7 > seq(from=1, to=7, by=1) [1] 1 2 3 4 5 6 7 > seq(from=1, to=7, by=1/3) [1] 1.000000 1.333333 1.666667 2.000000 2.333333 2.666667 3.000000 3.333333 3.666667 4.000000 4.333333 4.666667 [13] 5.000000 5.333333 5.666667 6.000000 6.333333 6.666667 7.000000 > seq(from=1, to=7, by=0.25) [1] 1.00 1.25 1.50 1.75 2.00 2.25 2.50 2.75 3.00 3.25 3.50 3.75 4.00 4.25 4.50 4.75 5.00 5.25 5.50 5.75 6.00 6.25 6.50 [24] 6.75 7.00 > rep(1, times=10) [1] 1 1 1 1 1 1 1 1 1 1 > rep("marin", times=5) [1] "marin" "marin" "marin" "marin" "marin" > rep(1:3, times=5) [1] 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 > rep(seq(from=2, to=5, by=0.75), times=5) [1] 2.00 2.75 3.50 4.25 5.00 2.00 2.75 3.50 4.25 5.00 2.00 2.75 3.50 4.25 5.00 2.00 2.75 3.50 4.25 5.00 2.00 2.75 3.50 [24] 4.25 5.00 > rep(c("m", "f"), times=5) [1] "m" "f" "m" "f" "m" "f" "m" "f" "m" "f" > x <- 1:5 > y <- c(1,3,5,7,9) > y [1] 1 3 5 7 9 > x [1] 1 2 3 4 5 > x + 10 [1] 11 12 13 14 15 > x - 10 [1] -9 -8 -7 -6 -5 > x * 10 [1] 10 20 30 40 50 > x/2 [1] 0.5 1.0 1.5 2.0 2.5 > x + y [1] 2 5 8 11 14 > x-y [1] 0 -1 -2 -3 -4 > x*y [1] 1 6 15 28 45 > x/y [1] 1.0000000 0.6666667 0.6000000 0.5714286 0.5555556 > > x [1] 1 2 3 4 5 > y [1] 1 3 5 7 9 > y[3] [1] 5 > y[-3] [1] 1 3 7 9 > y[1:3] [1] 1 3 5 > y[c(1,5)] [1] 1 9 > y[-c(1,5)] [1] 3 5 7 > y[y<6] [1] 1 3 5 > y[x<6] [1] 1 3 5 7 9 > matrix(1:9, nrow=3, byrow=TRUE) [,1] [,2] [,3] [1,] 1 2 3 [2,] 4 5 6 [3,] 7 8 9 > mat <- matrix(1:9, nrow=3, byrow=FALSE) > mat [,1] [,2] [,3] [1,] 1 4 7 [2,] 2 5 8 [3,] 3 6 9 > mat <- matrix(1:9, nrow=3, byrow=TRUE) > mat [,1] [,2] [,3] [1,] 1 2 3 [2,] 4 5 6 [3,] 7 8 9 > mat[1, 2] [1] 2 > mat[c(1,3), 2] [1] 2 8 > mat[2] [1] 4 > mat[2,] [1] 4 5 6 > mat[,1] [1] 1 4 7 > mat*10 [,1] [,2] [,3] [1,] 10 20 30 [2,] 40 50 60 [3,] 70 80 90