数据分析项目可能需要一些我们通常认为简单的东西，但实际上对实现目标很有帮助，其中之一就是添加R数据框的值或列。要将一列添加到其余的下一列中，我们可以通过使用单个方括号添加一列来替换下一列。
考虑以下数据帧-
x1<-rnorm(20) x2<-rnorm(20) x3<-rnorm(20) x4<-rnorm(20) df1<-data.frame(x1,x2,x3,x4) df1输出结果
x1 x2 x3 x4 1 1.85664999 -0.9065488762 0.293178644 0.55457359 2 0.44698508 0.9893899854 0.536684098 0.28302308 3 0.61888012 -0.4300288618 1.030952802 -0.25713481 4 -0.05365888 1.1227376933 1.382627238 2.00689788 5 0.03964954 2.2557976594 -0.902402177 -1.58164559 6 -0.66872443 -0.0004653294 2.125212420 -1.10464733 7 0.03000691 -0.7238778598 -0.669792673 0.30548849 8 -0.43260468 0.4872185286 0.197004732 -1.84113665 9 -0.95276898 -1.0384948791 -0.007177681 -1.59672437 10 -0.83272853 0.5075483877 0.585314160 0.72559385 11 -0.23842261 0.2950442950 0.593196270 -0.11921104 12 -0.17180004 -0.0105962399 0.927656280 -1.07630231 13 0.26177947 -0.2539494068 0.333217120 0.62433826 14 0.42988050 -0.5740571129 -0.727895313 -0.58763643 15 0.47914315 -0.3317974395 -1.502326687 -0.12933857 16 0.72317202 0.4056645753 0.720629400 1.51496596 17 -0.63108679 1.1358016229 -0.467778438 0.40033389 18 -0.39403524 -1.3937678989 -1.579988055 1.61907436 19 0.38662052 -0.2191345379 0.409531230 -2.50333812 20 -0.34579323 0.2170208774 0.441002799 0.08652698
将第1列添加到df1中的第2到第4列-
df1[2:ncol(df1)]<-df1[2:ncol(df1)]+df1[,1] df1输出结果
x1 x2 x3 x4 1 1.85664999 0.950101112 2.14982863 2.4112236 2 0.44698508 1.436375070 0.98366918 0.7300082 3 0.61888012 0.188851261 1.64983293 0.3617453 4 -0.05365888 1.069078817 1.32896836 1.9532390 5 0.03964954 2.295447201 -0.86275264 -1.5419960 6 -0.66872443 -0.669189755 1.45648799 -1.7733718 7 0.03000691 -0.693870954 -0.63978577 0.3354954 8 -0.43260468 0.054613849 -0.23559995 -2.2737413 9 -0.95276898 -1.991263856 -0.95994666 -2.5494933 10 -0.83272853 -0.325180141 -0.24741437 -0.1071347 11 -0.23842261 0.056621690 0.35477366 -0.3576336 12 -0.17180004 -0.182396283 0.75585624 -1.2481024 13 0.26177947 0.007830061 0.59499659 0.8861177 14 0.42988050 -0.144176615 -0.29801481 -0.1577559 15 0.47914315 0.147345709 -1.02318354 0.3498046 16 0.72317202 1.128836595 1.44380142 2.2381380 17 -0.63108679 0.504714834 -1.09886523 -0.2307529 18 -0.39403524 -1.787803135 -1.97402329 1.2250391 19 0.38662052 0.167485982 0.79615175 -2.1167176 20 -0.34579323 -0.128772348 0.09520957 -0.2592662
y1<-rpois(20,5) y2<-rpois(20,5) y3<-rpois(20,5) y4<-rpois(20,5) y5<-rpois(20,5) df2<-data.frame(y1,y2,y3,y4,y5) df2输出结果
y1 y2 y3 y4 y5 1 11 5 3 2 9 2 7 4 6 11 3 3 2 4 3 5 5 4 3 4 3 8 5 5 7 5 6 6 3 6 3 4 5 6 8 7 4 6 5 7 4 8 6 4 6 5 3 9 6 2 4 8 8 10 7 8 3 3 4 11 2 10 01 2 5 12 7 7 2 6 1 13 8 5 6 3 2 14 5 5 4 9 4 15 5 5 6 5 7 16 6 4 8 9 4 17 3 3 5 9 0 18 5 4 3 5 2 19 5 6 9 11 4 20 4 4 3 4 10
将第1列添加到df2中的第2至5列-
df2[2:ncol(df2)]<-df2[2:ncol(df2)]+df2[,1] df2输出结果
y1 y2 y3 y4 y5 1 11 16 14 13 20 2 7 11 13 18 10 3 2 6 5 7 7 4 3 7 6 11 8 5 7 12 13 13 10 6 3 7 8 9 11 7 4 10 9 11 8 8 6 10 12 11 9 9 6 8 10 14 14 10 7 15 10 10 11 11 2 12 3 4 7 12 7 14 9 13 8 13 8 13 14 11 10 14 5 10 9 14 9 15 5 10 11 10 12 16 6 10 14 15 10 17 3 6 8 12 3 18 5 9 8 10 7 19 5 11 14 16 9 20 4 8 7 8 14