Applying is.logical to a list with multiple data types

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I'm trying to figure out how to do some data quality checking on a code.

Suppose I have

x <- list(1,2,T)
y <- list(1,2,3)

I want to be able to apply a function which will flag 'x' as having bad data.

if(any(is.logical(x))) stop('Bad data')

but

if(any(is.logical(y)))

won't trigger an error.

I know I could do it with a for loop, but I'm hoping to find a simpler solution.

For Loop Solution

for (tmp in x) {if (is.logical(tmp)) stop('Bad data')}
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There are 1 answers

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Shuo On BEST ANSWER

solution is to use sapply.

> any(sapply(x,is.logical))
[1] TRUE

> any(sapply(y,is.logical))
[1] FALSE 

Note that using any and sapply is significantly slower than using a for loop.

> system.time(any(sapply(x,is.logical)))
  user  system elapsed 
  1.58    0.02    1.61 

> system.time(for (blah in x) {if(is.logical(x)) {}})
  user  system elapsed 
  0.29    0.00    0.29

Using vapply as suggested below

> system.time(any(vapply(x, is.logical, logical(1))))
  user  system elapsed 
  0.30    0.01    0.28