You could also try the following package: DMwR.
It failed on the case of 3 NN, giving 'Error in knnImputation(x, k = 3) :
Not sufficient complete cases for computing neighbors.'
However, trying 2 gives.
> knnImputation(x,k=2)
[,1] [,2] [,3] [,4] [,5] [,6]
[1,] -0.59091360 -1.2698175 0.5556009 -0.1327224 -0.8325065 0.71664000
[2,] -1.27255074 -0.7853602 0.7261897 0.2969900 0.2969556 -0.44612831
[3,] 0.55473981 0.4748735 0.5158498 -0.9493917 -1.5187722 -0.99377854
[4,] -0.47797654 0.1647818 0.6167311 -0.5149731 0.5240514 -0.46027809
[5,] -1.08767831 -0.3785608 0.6659499 -0.7223724 -0.9512409 -1.60547053
[6,] -0.06153279 0.9486815 -0.5464601 0.1544475 0.2835521 -0.82250221
[7,] -0.82536029 -0.2906253 -3.0284281 -0.8473210 0.7985286 -0.09751927
[8,] -1.15366189 0.5341000 -1.0109258 -1.5900281 0.2742328 0.29039928
[9,] -1.49504465 -0.5419533 0.5766574 -1.2412777 -1.4089572 -0.71069839
[10,] -0.35935440 -0.2622265 0.4048126 -2.0869817 0.2682486 0.16904559
[,7] [,8] [,9] [,10]
[1,] 0.58027159 -1.0669137 0.48670802 0.5824858
[2,] -0.48314440 -1.0532693 -0.34030385 -1.1041681
[3,] -2.81996446 0.3191438 -0.48117020 -0.0352633
[4,] -0.55080515 -1.0620243 -0.51383557 0.3161907
[5,] -0.56808769 -0.3696951 0.35549191 0.3202675
[6,] -0.25043479 -1.0389393 0.07810902 0.5251606
[7,] -0.41667318 0.8809541 -0.04613332 -1.1586756
[8,] -0.06898363 -1.0736161 0.62698065 -1.0373835
[9,] 0.30051583 -0.2936140 0.31417921 -1.4155193
[10,] -0.68180034 -1.0789745 0.58290920 -1.0197956
You can test for sufficient observations using complete.cases(x),
where that value must be at least k.
One way to overcome this problem is to relax your requirements (i.e. less incomplete rows),
by 1) increasing the NA threshold, or alternatively, 2) increasing your number of observations.
Here is the first:
> x = matrix(rnorm(100),10,10)
> x.missing = x > 2
> x[x.missing] = NA
> complete.cases(x)
[1] TRUE TRUE TRUE FALSE FALSE TRUE TRUE TRUE TRUE TRUE
> knnImputation(x,k=3)
[,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10]
[1,] 0.86882569 -0.2409922 0.3859031 0.5818927 -1.50310330 0.8752261 -0.5173105 -2.18244988 -0.28817656 -0.63941237
[2,] 1.54114079 0.7227511 0.7856277 0.8512048 -1.32442954 -2.1668744 0.7017532 -0.40086348 -0.41251883 0.42924986
[3,] 0.60062917 -0.5955623 0.6192783 -0.3836310 0.06871570 1.7804657 0.5965411 -1.62625036 1.27706937 0.72860273
[4,] -0.07328279 -0.1738157 1.4965579 -1.1686115 -0.06954318 -1.0171604 -0.3283916 0.63493884 0.72039689 -0.20889111
[5,] 0.78747874 -0.8607320 0.4828322 0.6558960 -0.22064430 0.2001473 0.7725701 0.06155196 0.09011719 -1.01902968
[6,] 0.17988720 -0.8520000 -0.5911523 1.8100573 -0.56108621 0.0151522 -0.2484345 -0.80695513 -0.18532984 -1.75115335
[7,] 1.03943492 0.4880532 -2.7588922 -0.1336166 -1.28424057 1.2871333 0.7595750 -0.55615677 -1.67765572 -0.05440992
[8,] 1.12394474 1.4890366 -1.6034648 -1.4315445 -0.23052386 -0.3536677 -0.8694188 -0.53689507 -1.11510406 -1.39108817
[9,] -0.30393916 0.6216156 0.1559639 1.2297105 -0.29439390 1.8224512 -0.4457441 -0.32814665 0.55487894 -0.22602598
[10,] 1.18424722 -0.1816049 -2.2975095 -0.7537477 0.86647524 -0.8710603 0.3351710 -0.79632184 -0.56254688 -0.77449398
> x
[,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10]
[1,] 0.86882569 -0.2409922 0.3859031 0.5818927 -1.5031033 0.8752261 -0.5173105 -2.18244988 -0.28817656 -0.63941237
[2,] 1.54114079 0.7227511 0.7856277 0.8512048 -1.3244295 -2.1668744 0.7017532 -0.40086348 -0.41251883 0.42924986
[3,] 0.60062917 -0.5955623 0.6192783 -0.3836310 0.0687157 1.7804657 0.5965411 -1.62625036 1.27706937 0.72860273
[4,] -0.07328279 -0.1738157 1.4965579 -1.1686115 NA -1.0171604 -0.3283916 0.63493884 0.72039689 -0.20889111
[5,] 0.78747874 -0.8607320 0.4828322 NA -0.2206443 0.2001473 0.7725701 0.06155196 0.09011719 -1.01902968
[6,] 0.17988720 -0.8520000 -0.5911523 1.8100573 -0.5610862 0.0151522 -0.2484345 -0.80695513 -0.18532984 -1.75115335
[7,] 1.03943492 0.4880532 -2.7588922 -0.1336166 -1.2842406 1.2871333 0.7595750 -0.55615677 -1.67765572 -0.05440992
[8,] 1.12394474 1.4890366 -1.6034648 -1.4315445 -0.2305239 -0.3536677 -0.8694188 -0.53689507 -1.11510406 -1.39108817
[9,] -0.30393916 0.6216156 0.1559639 1.2297105 -0.2943939 1.8224512 -0.4457441 -0.32814665 0.55487894 -0.22602598
[10,] 1.18424722 -0.1816049 -2.2975095 -0.7537477 0.8664752 -0.8710603 0.3351710 -0.79632184 -0.56254688 -0.77449398
here is an example of the 2nd...
x = matrix(rnorm(1000),100,10)
x.missing = x > 1
x[x.missing] = NA
complete.cases(x)
[1] TRUE FALSE FALSE FALSE TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE TRUE FALSE FALSE FALSE TRUE FALSE FALSE
[22] FALSE FALSE TRUE FALSE TRUE TRUE FALSE FALSE FALSE FALSE FALSE FALSE TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
[43] TRUE FALSE FALSE TRUE FALSE FALSE FALSE TRUE FALSE FALSE TRUE FALSE TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
[64] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE TRUE
[85] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE TRUE TRUE FALSE
At least k=3 complete rows are satisfied, thus it is able to impute for k=3.
> head(knnImputation(x,k=3))
[,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10]
[1,] 0.01817557 -2.8141502 0.3929944 0.1495092 -1.7218396 0.4159133 -0.8438809 0.6599224 -0.02451113 -1.14541016
[2,] 0.51969964 -0.4976021 -0.1495392 -0.6448184 -0.6066386 -1.6210476 -0.3118440 0.2477855 -0.30986749 0.32424673
...
Best Answer
kmeans() (you can find it by typing
??
followed by the name of what you want as in??kmean
). In general, a good trick is to first look it up on a R specific search engine