seq（）を関数の条件として挿入するにはどうすればよいですか？

Question

は、私はこのデータを持っていると仮定します

set.seed(1234) 
cMat <- matrix(rnorm(10),5,2) 
clist <- replicate(39, cMat + rnorm(10), simplify=FALSE) 

[[1]] 
      [,1]  [,2] 
[1,] -1.6842584 0.3957704 
[2,] -0.7209572 -1.0857495 
[3,] 0.3081873 -1.4578273 
[4,] -2.2812389 -1.4016237 
[5,] 1.3886187 1.5257973 

[[2]] 
      [,1]   [,2] 
[1,] -1.0729775 -9.421490e-01 
[2,] -0.2132567 1.576077e-05 
[3,] 0.6438933 -1.570288e+00 
[4,] -1.8861083 -5.795903e-01 
[5,] -0.2645956 -1.825986e+00 

[[3]] 
      [,1]  [,2] 
[1,] -0.1047682 -0.6615634 
[2,] -0.1981638 -2.7547796 
[3,] 0.3750011 -1.8876250 
[4,] -2.8469558 -0.8587459 
[5,] -1.1999688 -1.3559354 

[[4]] 
      [,1]  [,2] 
[1,] 0.2424305 -0.4624584 
[2,] -0.7912135 -1.6820582 
[3,] 0.2290765 -1.7986177 
[4,] -2.6263207 -1.0882801 
[5,] -0.5652154 -1.3868878 

[[5]] 
      [,1]  [,2] 
[1,] -3.01309701 1.069112 
[2,] -0.30464668 1.073078 
[3,] -0.02444845 -1.319985 
[4,] -3.36065971 1.041458 
[5,] 0.26681517 -2.047846 

[[6]] 
      [,1]  [,2] 
[1,] -0.5504773 2.2831403 
[2,] 2.8264203 -1.7133477 
[3,] 1.0496808 0.8211953 
[4,] -3.0153313 0.7651128 
[5,] 0.4215199 -0.5535650 

[[7]] 
      [,1]  [,2] 
[1,] -1.2001729 0.3526575 
[2,] -0.1780395 -1.9654409 
[3,] 0.7179172 -1.2702136 
[4,] -1.6974111 -0.3061902 
[5,] 2.4993956 -1.2070969 

[[8]] 
      [,1]  [,2] 
[1,] -1.3848557 1.20366460 
[2,] 0.1074352 -0.02474261 
[3,] -0.2878607 -0.94936383 
[4,] -2.5194849 -0.75604577 
[5,] 1.2793569 -2.08456571 

[[9]] 
      [,1]  [,2] 
[1,] -1.26022457 0.8616062 
[2,] 0.53262524 -1.7093480 
[3,] 2.79040518 0.3315718 
[4,] -1.34418445 0.4084648 
[5,] -0.06645875 1.2310793 

[[10]] 
      [,1]  [,2] 
[1,] -0.7925422 0.6730452 
[2,] -0.1972892 -1.4710046 
[3,] 1.1504347 -0.3784465 
[4,] -2.8481755 -0.2094837 
[5,] -0.3968739 -0.9421429 

[[11]] 
      [,1]  [,2] 
[1,] -1.40300037 1.3371965 
[2,] -0.37164051 -1.8190278 
[3,] -0.02532605 -0.3776054 
[4,] -1.49642350 0.1087143 
[5,] 0.45148721 -0.9163142 

[[12]] 
      [,1]  [,2] 
[1,] -1.3984579 0.5861155 
[2,] -0.5044774 -1.2061493 
[3,] 3.1426032 -2.0599200 
[4,] -1.5951962 -1.2005518 
[5,] 2.2533330 -0.6637363 

[[13]] 
      [,1]  [,2] 
[1,] -0.19337540 0.1402036 
[2,] 0.53017938 -0.8908583 
[3,] -0.08750714 -2.4948779 
[4,] -1.67698337 0.3556055 
[5,] -1.22097625 -1.5129094 

[[14]] 
      [,1]  [,2] 
[1,] -1.5411024 0.90532770 
[2,] 1.6725771 1.08811649 
[3,] 1.7211156 -0.27073845 
[4,] -2.4541294 -0.05817938 
[5,] 0.9428875 -0.54248585 

[[15]] 
      [,1]  [,2] 
[1,] -1.5843034 1.868187 
[2,] 0.3750487 -0.809361 
[3,] 2.7231858 -1.600015 
[4,] -3.2212902 -1.434236 
[5,] 0.5508847 -1.280165 

[[16]] 
      [,1]  [,2] 
[1,] -2.05441582 1.1306890 
[2,] 0.01678985 1.1034658 
[3,] 0.67002147 -0.6153255 
[4,] -2.52874850 -0.8852919 
[5,] 0.83618079 0.5809679 

[[17]] 
      [,1]  [,2] 
[1,] 0.4972636 -0.3315265 
[2,] 0.3206733 -1.6985028 
[3,] 0.7517839 2.4971340 
[4,] -4.1679331 -0.3294307 
[5,] 1.8403871 -0.9232964 

[[18]] 
      [,1]  [,2] 
[1,] -3.9392853 2.4897881 
[2,] 0.1776387 0.5943686 
[3,] 2.0604729 -1.0553689 
[4,] -1.9318288 0.1397282 
[5,] 1.3414469 -1.0884541 

[[19]] 
      [,1]  [,2] 
[1,] -1.7451365 1.00675051 
[2,] -2.5783294 0.04547024 
[3,] 0.2947943 -1.51253507 
[4,] -1.8578831 -0.40179729 
[5,] 2.5971572 -2.96827537 

[[20]] 
      [,1]  [,2] 
[1,] -0.7218389 1.266518 
[2,] 0.9741980 1.267724 
[3,] 1.2699551 0.565731 
[4,] -1.6449642 -0.531788 
[5,] 0.7408057 -2.004487 

[[21]] 
      [,1]  [,2] 
[1,] -0.7890079 0.9280643 
[2,] -0.1228060 -0.7264765 
[3,] 2.5779343 -1.1527830 
[4,] -3.9527786 -0.8691731 
[5,] 0.0133729 -0.2605017 

[[22]] 
      [,1]  [,2] 
[1,] -0.3118938 -0.1537142 
[2,] 0.9376419 2.3444002 
[3,] 3.3579247 0.1307836 
[4,] -1.1722001 -1.2487723 
[5,] 0.7168344 -0.7035457 

[[23]] 
      [,1]  [,2] 
[1,] -1.531459050 -0.5714862 
[2,] 0.002725024 -3.8078921 
[3,] 0.150937836 -0.8015065 
[4,] -2.228852358 -0.5349342 
[5,] 0.748284927 -0.2957641 

[[24]] 
      [,1]  [,2] 
[1,] -1.1479306 0.7577070 
[2,] 0.6908281 0.7825345 
[3,] -0.0133310 -0.1421634 
[4,] -1.6345224 -0.3000877 
[5,] 1.1480134 -0.6219939 

[[25]] 
      [,1]  [,2] 
[1,] -0.7701352 0.1355584 
[2,] 1.3375531 0.9022296 
[3,] 1.5366316 -1.7705356 
[4,] -1.6824991 -0.3063836 
[5,] -0.7072489 -0.4850350 

[[26]] 
      [,1]  [,2] 
[1,] -0.23126243 -0.1605091 
[2,] -0.07144749 -0.8133866 
[3,] 1.24306662 -1.7343971 
[4,] -4.10895277 -0.1795167 
[5,] 0.76772074 -0.2234583 

[[27]] 
      [,1]  [,2] 
[1,] -1.511680 -0.1450577 
[2,] 2.102440 0.2338793 
[3,] 1.755001 0.4399488 
[4,] -1.397065 -0.5706228 
[5,] 2.478528 -0.5709855 

[[28]] 
      [,1]  [,2] 
[1,] -2.2188877 0.8254534 
[2,] 0.7475968 -1.4212626 
[3,] 0.3834708 -0.7923950 
[4,] -1.5320148 -2.1173110 
[5,] -0.3823061 -0.7616038 

[[29]] 
      [,1]  [,2] 
[1,] -0.2216224 2.3158613 
[2,] 0.4606768 -1.7497767 
[3,] -0.6817880 -0.9133351 
[4,] -2.9662314 -0.2108266 
[5,] 2.0851677 -0.5708816 

[[30]] 
      [,1]  [,2] 
[1,] -1.7870227 -0.1429723 
[2,] -0.6758495 -1.0791142 
[3,] 0.9050126 1.0677596 
[4,] -1.3358895 -1.0114118 
[5,] 0.4527513 -0.1268611 

[[31]] 
      [,1]  [,2] 
[1,] 0.26465294 1.7337730 
[2,] 0.72109415 -0.7242935 
[3,] 0.66271931 1.0033515 
[4,] -2.38569933 -1.1260645 
[5,] -0.06315528 -1.5371551 

[[32]] 
      [,1]  [,2] 
[1,] -1.0639336 -0.2105208 
[2,] 0.3016179 0.5078710 
[3,] 0.5799897 -1.4993173 
[4,] -3.9270945 0.5620307 
[5,] 0.4591911 -1.5390808 

[[33]] 
      [,1]  [,2] 
[1,] -0.9145957 -0.6291570 
[2,] 1.1761320 -0.8448196 
[3,] 0.5656988 1.0731580 
[4,] -1.7912592 -0.7785832 
[5,] 0.3411510 -1.7078203 

[[34]] 
      [,1]  [,2] 
[1,] -1.2610887 1.670631 
[2,] 0.6075709 -1.339000 
[3,] 2.0397658 -2.891145 
[4,] -1.2017378 -1.036135 
[5,] 0.5296471 -1.405893 

[[35]] 
      [,1]  [,2] 
[1,] -3.523102 1.0535801 
[2,] 0.839901 1.3164871 
[3,] 0.300666 -1.4247090 
[4,] -2.571752 -0.6770109 
[5,] -1.157978 1.0586752 

[[36]] 
      [,1]  [,2] 
[1,] -0.27324942 1.9406296 
[2,] 2.19048866 -1.8605785 
[3,] 1.07920712 -0.2393176 
[4,] -2.49795775 -0.6107705 
[5,] -0.08050697 1.3618040 

[[37]] 
      [,1]  [,2] 
[1,] -1.8150995 0.63834698 
[2,] -1.2318589 -0.85026471 
[3,] 1.3170729 -1.22539050 
[4,] -2.3853464 -0.06361607 
[5,] -0.4100004 -1.22170014 

[[38]] 
      [,1]  [,2] 
[1,] -3.0420460 1.7211095 
[2,] -2.3743120 0.4077655 
[3,] 0.5038590 -0.2308678 
[4,] -0.8915108 -2.0715146 
[5,] 1.2672541 -0.6844680 

[[39]] 
      [,1]  [,2] 
[1,] 0.3901623 1.29545030 
[2,] -3.1186343 -0.11764045 
[3,] 0.3030889 -0.00779874 
[4,] -1.2432331 -0.54980888 
[5,] 0.9578697 -1.80652696 

そして、この単純な関数は、リスト内の各マトリックスに適用するために、私は、このコードで使用

testfunction <- function(X) 
{ 
newX <- X[c(1:5),]*2 
return(newX) 
} 

：clistnew <- lapply(clist, testfunction)

私は条件を追加したい - 私は次のシーケンスの行列の行に2の代わりに3を掛けたい：

mysequence = seq(8,length(clist) ,by=13) 
[1] 8 21 34 

私はこれにコードを変更すると

testfunction <- function(X) 
{ 
newX <- X[c(1:5),]*2 
for(i in seq(8,length(X) ,by=13)){ 
newX <- X[c(1:5),]*3 
} 
return(newX) 
} 

を働くだろうと思ったしかし、その代わりに、それは、コードの前の行を無視して、3ですべての行列の行を乗算します。私は解決策が簡単だと確信していますが、私は初心者ですが、残念ながら私はそれを理解できません。

Answer 1

私が正しく理解していれば、以下はあなたが望むことをするでしょう。

testfunction <- function(i, X, myseq){ 
    if(i %in% myseq) 
     newX <- X[1:5, ]*3 
    else 
     newX <- X[1:5, ]*2 
    newX 
} 

mysequence = seq(8, length(clist), by = 13) 

lapply(seq_along(clist), function(i) testfunction(i, clist[[i]], mysequence))