2012-08-03 99 views
11

我有一個關於每行計數零的問題。我有這樣一個數據幀:計算每行零數,並刪除多於n個零的行

a = c(1,2,3,4,5,6,0,2,5) 
b = c(0,0,0,2,6,7,0,0,0) 
c = c(0,5,2,7,3,1,0,3,0) 
d = c(1,2,6,3,8,4,0,4,0) 
e = c(0,4,6,3,8,4,0,6,0) 
f = c(0,2,5,5,8,4,2,7,4) 
g = c(0,8,5,4,7,4,0,0,0) 
h = c(1,3,6,7,4,2,0,4,2) 
i = c(1,5,3,6,3,7,0,5,3) 
j = c(1,5,2,6,4,6,8,4,2) 

DF<- data.frame(a=a,b=b,c=c,d=d,e=e,f=f,g=g,h=h,i=i,j=j) 

    a b c d e f g h i j 
1 1 0 0 1 0 0 0 1 1 1 
2 2 0 5 2 4 2 8 3 5 5 
3 3 0 2 6 6 5 5 6 3 2 
4 4 2 7 3 3 5 4 7 6 6 
5 5 6 3 8 8 8 7 4 3 4 
6 6 7 1 4 4 4 4 2 7 6 
7 0 0 0 0 0 2 0 0 0 8 
8 2 0 3 4 6 7 0 4 5 4 
9 5 0 0 0 0 4 0 2 3 2 

我想統計每行零的數量。如果每行的零數大於某個數字,比如4,我想刪除整行。生成的數據幀如下所示:

a b c d e f g h i j 
2 2 0 5 2 4 2 8 3 5 5 
3 3 0 2 6 6 5 5 6 3 2 
4 4 2 7 3 3 5 4 7 6 6 
5 5 6 3 8 8 8 7 4 3 4 
6 6 7 1 4 4 4 4 2 7 6 
8 2 0 3 4 6 7 0 4 5 4 

這可能嗎?謝謝!

回答

29

這不僅是可能的,但很容易:

DF[rowSums(DF == 0) <= 4, ] 

您也可以使用apply

DF[apply(DF == 0, 1, sum) <= 4, ]