Menu
Possible Duplicate:
Removing empty rows of a data file in R
How would I remove rows from a matrix or data frame where all elements in the row are NA?
So to get from this:
[,1] [,2] [,3] [1,] 1 6 11 [2,] NA NA NA [3,] 3 8 13 [4,] 4 NA NA [5,] 5 10 NA to this:
[,1] [,2] [,3] [1,] 1 6 11 [2,] 3 8 13 [3,] 4 NA NA [4,] 5 10 NA Because the problem with na.omit is that it removes rows with any NAs and so would give me this:
[,1] [,2] [,3] [1,] 1 6 11 [2,] 3 8 13 The best I have been able to do so far is use the apply() function:
> x[apply(x, 1, function(y) !all(is.na(y))),] [,1] [,2] [,3] [1,] 1 6 11 [2,] 3 8 13 [3,] 4 NA NA [4,] 5 10 NA but this seems quite convoluted (is there something simpler that I am missing?)....
Thanks.
472
To remove all rows having NA, we can use na. omit function. For Example, if we have a data frame called df that contains some NA values then we can remove all rows that contains at least one NA by using the command na. omit(df).
To remove the multiple rows in R, use the subsetting and pass the vector with multiple elements. The elements are the row index, which we need to remove. To remove the second and third-row in R, use -c(2, 3), and it will return the data frame without the second and third row.
We use the matrix() function and pass the parameter values of its shape. nrow = 3 represents 3 rows, while ncol = 2 represents 2 columns. Line 4: Using the c() function, we remove the first row and first column [-c(1), -c(1)] from the matrix.
Solutions using rowSums() generally outperform apply() ones:
m <- structure(c( 1, NA, 3, 4, 5, 6, NA, 8, NA, 10, 11, NA, 13, NA, NA), .Dim = c(5L, 3L)) m[rowSums(is.na(m)) != ncol(m), ] [,1] [,2] [,3] [1,] 1 6 11 [2,] 3 8 13 [3,] 4 NA NA [4,] 5 10 NA Sweep a test for all(is.na()) across rows, and remove where true. Something like this (untested as you provided no code to generate your data -- dput() is your friend):
R> ind <- apply(X, 1, function(x) all(is.na(x))) R> X <- X[ !ind, ] If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
