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Type 'q()' to quit R. > x <- c(10,20,30,40) > names(x) <- c(1,2,3,4) > x 1 2 3 4 10 20 30 40 > x 1 2 3 4 10 20 30 40 > names(x) <- NULL > x [1] 10 20 30 40 > x + 1 [1] 11 21 31 41 > x>15 [1] FALSE TRUE TRUE TRUE > sqrt(x) [1] 3.162278 4.472136 5.477226 6.324555 > y <- rivers[1:10] > y [1] 735 320 325 392 524 450 1459 135 465 600 > sort(y) [1] 135 320 325 392 450 465 524 600 735 1459 > ?sort > sort(y,decreasing=TRUE) [1] 1459 735 600 524 465 450 392 325 320 135 > > > > x<- c(1, 2, 3, 4, 5, 6); y <- c(1, 2, 3); z <-c(1, 2, 3, 4) > length(x) [1] 6 > length(y) [1] 3 > length(z) [1] 4 > > x+y [1] 2 4 6 5 7 9 > x+z [1] 2 4 6 8 6 8 Warning message: In x + z : longer object length is not a multiple of shorter object length > > > > y <- rivers > length(y) [1] 141 > x <- c(1,5,10,15,20,25) > x[2] [1] 5 > x[c(2,4,6)] [1] 5 15 25 > x[c(2,4,6,8)] [1] 5 15 25 NA > x[-2] [1] 1 10 15 20 25 > x[-c(2,4,6,8)] [1] 1 10 20 > x [1] 1 5 10 15 20 25 > x[c(T,F,F,F,T,T)] [1] 1 20 25 > x[c(T,F)] [1] 1 10 20 > x[c(T,F,F,F)] [1] 1 20 > ?c > x[c('Paul','John')] [1] NA NA > #recall the airquality data > airquality$Ozone [1] 41 36 12 18 NA 28 23 19 8 NA 7 16 11 [14] 14 18 14 34 6 30 11 1 11 4 32 NA NA [27] NA 23 45 115 37 NA NA NA NA NA NA 29 NA [40] 71 39 NA NA 23 NA NA 21 37 20 12 13 NA [53] NA NA NA NA NA NA NA NA NA 135 49 32 NA [66] 64 40 77 97 97 85 NA 10 27 NA 7 48 35 [79] 61 79 63 16 NA NA 80 108 20 52 82 50 64 [92] 59 39 9 16 78 35 66 122 89 110 NA NA 44 [105] 28 65 NA 22 59 23 31 44 21 9 NA 45 168 [118] 73 NA 76 118 84 85 96 78 73 91 47 32 20 [131] 23 21 24 44 21 28 9 13 46 18 13 24 16 [144] 13 23 36 7 14 30 NA 14 18 20 > > small <- rivers <= 500 > small [1] FALSE TRUE TRUE TRUE FALSE TRUE FALSE TRUE [9] TRUE FALSE TRUE TRUE TRUE TRUE FALSE FALSE [17] TRUE TRUE TRUE FALSE FALSE FALSE FALSE FALSE [25] FALSE FALSE TRUE TRUE TRUE TRUE FALSE FALSE [33] TRUE TRUE TRUE TRUE TRUE FALSE TRUE FALSE [41] TRUE TRUE TRUE FALSE FALSE TRUE TRUE TRUE [49] TRUE FALSE TRUE TRUE TRUE TRUE TRUE TRUE [57] TRUE FALSE FALSE TRUE TRUE FALSE FALSE FALSE [65] TRUE FALSE FALSE FALSE FALSE FALSE FALSE TRUE [73] TRUE TRUE TRUE TRUE TRUE TRUE FALSE FALSE [81] TRUE FALSE FALSE TRUE FALSE FALSE TRUE TRUE [89] FALSE FALSE TRUE TRUE TRUE TRUE TRUE TRUE [97] TRUE FALSE FALSE TRUE FALSE TRUE TRUE TRUE [105] TRUE TRUE TRUE TRUE FALSE TRUE TRUE TRUE [113] FALSE FALSE FALSE TRUE TRUE FALSE TRUE FALSE [121] FALSE TRUE TRUE TRUE TRUE TRUE TRUE FALSE [129] TRUE FALSE FALSE FALSE TRUE TRUE FALSE TRUE [137] FALSE TRUE TRUE FALSE FALSE > rivers [1] 735 320 325 392 524 450 1459 135 465 600 [11] 330 336 280 315 870 906 202 329 290 1000 [21] 600 505 1450 840 1243 890 350 407 286 280 [31] 525 720 390 250 327 230 265 850 210 630 [41] 260 230 360 730 600 306 390 420 291 710 [51] 340 217 281 352 259 250 470 680 570 350 [61] 300 560 900 625 332 2348 1171 3710 2315 2533 [71] 780 280 410 460 260 255 431 350 760 618 [81] 338 981 1306 500 696 605 250 411 1054 735 [91] 233 435 490 310 460 383 375 1270 545 445 [101] 1885 380 300 380 377 425 276 210 800 420 [111] 350 360 538 1100 1205 314 237 610 360 540 [121] 1038 424 310 300 444 301 268 620 215 652 [131] 900 525 246 360 529 500 720 270 430 671 [141] 1770 > sum(small) [1] 84 > medium <- rivers > 500 & rivers <= 1000 > medium [1] TRUE FALSE FALSE FALSE TRUE FALSE FALSE FALSE [9] FALSE TRUE FALSE FALSE FALSE FALSE TRUE TRUE [17] FALSE FALSE FALSE TRUE TRUE TRUE FALSE TRUE [25] FALSE TRUE FALSE FALSE FALSE FALSE TRUE TRUE [33] FALSE FALSE FALSE FALSE FALSE TRUE FALSE TRUE [41] FALSE FALSE FALSE TRUE TRUE FALSE FALSE FALSE [49] FALSE TRUE FALSE FALSE FALSE FALSE FALSE FALSE [57] FALSE TRUE TRUE FALSE FALSE TRUE TRUE TRUE [65] FALSE FALSE FALSE FALSE FALSE FALSE TRUE FALSE [73] FALSE FALSE FALSE FALSE FALSE FALSE TRUE TRUE [81] FALSE TRUE FALSE FALSE TRUE TRUE FALSE FALSE [89] FALSE TRUE FALSE FALSE FALSE FALSE FALSE FALSE [97] FALSE FALSE TRUE FALSE FALSE FALSE FALSE FALSE [105] FALSE FALSE FALSE FALSE TRUE FALSE FALSE FALSE [113] TRUE FALSE FALSE FALSE FALSE TRUE FALSE TRUE [121] FALSE FALSE FALSE FALSE FALSE FALSE FALSE TRUE [129] FALSE TRUE TRUE TRUE FALSE FALSE TRUE FALSE [137] TRUE FALSE FALSE TRUE FALSE > rivers[medium] [1] 735 524 600 870 906 1000 600 505 840 890 [11] 525 720 850 630 730 600 710 680 570 560 [21] 900 625 780 760 618 981 696 605 735 545 [31] 800 538 610 540 620 652 900 525 529 720 [41] 671 > mrivers <- rivers[medium] > mean(mrivers) [1] 692.561 > > > #creating vectors, take II > 1:10 [1] 1 2 3 4 5 6 7 8 9 10 > 16:29 [1] 16 17 18 19 20 21 22 23 24 25 26 27 28 29 > 29:20 [1] 29 28 27 26 25 24 23 22 21 20 > 5.5 : 10 [1] 5.5 6.5 7.5 8.5 9.5 > > > seq(from=8,to=7,by=-0.5) [1] 8.0 7.5 7.0 > seq(from=8,to=7,by=-0.1) [1] 8.0 7.9 7.8 7.7 7.6 7.5 7.4 7.3 7.2 7.1 7.0 > seq(from=8,to=7,by=0.1) Error in seq.default(from = 8, to = 7, by = 0.1) : wrong sign in 'by' argument > ?seq > seq(from=8,to=7,by=-0.2) [1] 8.0 7.8 7.6 7.4 7.2 7.0 > seq(by=-0.2, to=7, from=9) [1] 9.0 8.8 8.6 8.4 8.2 8.0 7.8 7.6 7.4 7.2 7.0 > seq(from=1,to=10,by=2) [1] 1 3 5 7 9 > seq(1,10,2) #shorthand [1] 1 3 5 7 9 > seq(2,10,1) #shorthand [1] 2 3 4 5 6 7 8 9 10 > seq(by=2,to=10,from=1) #shorthand [1] 1 3 5 7 9 >