Delete columns/rows with more than x% missing

Question

I want to delete all columns or rows with more than 50% NAs in a data frame.

This is my solution:

# delete columns with more than 50% mi         


        

Answer 1

A tidyverse solution that removes columns with an x% of NAs(50%) here:

test_data <- data.frame(A=c(rep(NA,12),
                            520,233,522),
                        B = c(rep(10,12),
                              520,233,522))
# Remove all with %NA >= 50
# can just use >50


 test_data %>% 
  purrr::discard(~sum(is.na(.x))/length(.x)* 100 >=50)

Result:

     B
1   10
2   10
3   10
4   10
5   10
6   10
7   10
8   10
9   10
10  10
11  10
12  10
13 520
14 233
15 522

Answer 2

To remove columns with some amount of NA, you can use colMeans(is.na(...))

## Some sample data
set.seed(0)
dat <- matrix(1:100, 10, 10)
dat[sample(1:100, 50)] <- NA
dat <- data.frame(dat)

## Remove columns with more than 50% NA
dat[, which(colMeans(!is.na(dat)) > 0.5)]

## Remove rows with more than 50% NA
dat[which(rowMeans(!is.na(dat)) > 0.5), ]

## Remove columns and rows with more than 50% NA
dat[which(rowMeans(!is.na(dat)) > 0.5), which(colMeans(!is.na(dat)) > 0.5)]