在分析项目中进行数据探索时,有时我们需要找到一些值的索引,主要是最小值和最大值的索引,以检查相应的数据行是否包含一些关键信息,或者我们可能会忽略它。此外,如果我们不想忽略它们,有时会根据数据特征将这些值转换为另一个值。
> x<-1:25 > which(x==min(x)) [1] 1 > which(x==max(x)) [1] 25 > set.seed(2) > x1<-sample(1:100,50,replace=TRUE) > x1 [1] 85 79 70 6 32 8 17 93 81 76 41 50 75 65 3 80 96 50 55 [20] 63 8 33 54 100 43 38 40 16 45 80 6 83 9 72 45 6 94 2 [39] 82 67 3 1 87 48 41 45 79 33 18 8 > which(x1==max(x1)) [1] 24 > which(x1==min(x1)) [1] 42 > x2<-sample(1:10,10,replace=TRUE) > x2 [1] 4 5 2 5 6 7 2 6 4 4 > which(x2==min(x2)) [1] 3 7 > which(x2==max(x2)) [1] 6 > x3<-rpois(50,10) > x3 [1] 11 9 13 8 8 9 10 7 6 9 13 10 9 6 8 12 13 15 4 13 12 8 8 14 15 [26] 11 12 9 8 8 11 8 8 8 9 8 7 13 17 9 8 11 15 15 6 12 5 16 10 7 > which(x3==max(x3)) [1] 39 > which(x3==min(x3)) [1] 19 > x4<-rpois(5,10) > x4 [1] 6 10 9 7 7 > which(x4==min(x4)) [1] 1 > which(x4==max(x4)) [1] 2 > x5<-rpois(200,10) > x5 [1] 12 16 8 8 6 9 13 9 13 8 10 7 7 8 12 15 10 8 14 11 12 3 10 14 8 [26] 9 7 8 11 7 10 8 8 9 9 5 13 9 12 7 4 12 11 10 12 11 7 7 5 13 [51] 9 4 13 13 12 10 11 7 10 13 12 10 11 14 6 15 11 7 4 9 5 10 12 14 6 [76] 7 12 10 4 10 6 11 5 11 10 13 8 15 5 5 13 16 7 7 10 7 9 12 8 17 [101] 14 14 12 9 9 5 10 8 9 19 13 11 12 8 10 10 8 8 11 8 9 8 12 11 9 [126] 9 13 9 14 9 8 20 12 8 13 15 15 3 10 15 9 13 8 10 16 12 14 8 14 15 [151] 13 10 14 9 6 10 12 5 8 11 11 5 12 4 11 8 7 13 7 11 8 3 8 11 13 [176] 10 10 9 8 13 12 11 10 11 13 16 14 9 12 9 9 12 13 9 12 9 14 11 10 11 > which(x5==max(x5)) [1] 132 > which(x5==min(x5)) [1] 22 138 172 > x6<-runif(50,2,5) > x6 [1] 2.296152 2.637028 3.774618 3.552248 4.292848 4.011675 3.202220 2.190245 [9] 3.124594 2.183614 4.511916 2.859132 4.388699 3.866623 3.947191 3.571981 [17] 4.781770 4.697633 4.242325 3.665438 3.067066 2.165258 4.817657 3.238631 [25] 4.970232 2.021909 4.757471 2.478177 2.519868 2.895012 4.392987 2.631473 [33] 4.306387 3.606730 3.647098 2.810375 4.820211 4.667225 4.768008 2.905660 [41] 3.079665 4.357212 2.927998 4.997810 2.089147 2.916278 2.381663 3.813988 [49] 2.971799 4.826013 > which(x6==min(x6)) [1] 26 > which(x6==max(x6)) [1] 44 > x7<-sample(200:1000,50,replace=TRUE) > x7 [1] 505 336 509 265 716 492 202 703 916 209 283 323 780 451 237 909 636 853 426 [20] 220 747 234 612 583 939 870 426 391 600 910 945 382 449 477 910 851 871 432 [39] 338 880 629 952 526 234 739 798 589 220 914 746 > which(x7==max(x7)) [1] 42 > which(x7==min(x7)) [1] 7