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rindexingapplyzero

Checking the presence of zeros in the first 3 non NA elements by row in R

I´m trying to delete the rows in a data frame which contain zeros in the first 3 non NA elements.

As example:

> c <- matrix(c(NA,NA,4,5,0,7,0,NA,NA,NA,NA,8,9,10,0,4,5,0,NA,NA), ncol=5, nrow = 4, byrow=T)
> c
     [,1] [,2] [,3] [,4] [,5]
[1,]   NA   NA    4    5    0
[2,]    7    0   NA   NA   NA
[3,]   NA    8    9   10    0
[4,]    4    5    0   NA   NA

I´m expecting to have an output such as: TRUE TRUE FALSE TRUE in order to create the subset without the rows with zeros in the first 3 non NA elements.

Does anyone have a simple solution for this?

Solution

  • We can do this with apply. Loop through the rows, subset the non-NA elements, check whether 0 is in it

    apply(c, 1, function(x) 0 %in% x[!is.na(x)][1:3])
#[1]  TRUE  TRUE FALSE  TRUE