[R] Testing if all elements are equal in a vector/matrix

[Patrick Burns]

How about

diff(range(x)) < tolerance

Patrick Burns
patrick at burns-stat.com
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http://www.burns-stat.com
(home of S Poetry and "A Guide for the Unwilling S User")

Vincent Goulet wrote:

>Is there a canonical way to check if all elements of a vector or matrix are 
>the same? Solutions below work, but look hackish to me.
>
>  
>
>>x <- rep(1, 10)
>>all(x == x[1])  # == operator does not provide for small differences
>>    
>>
>[1] TRUE
>  
>
>>isTRUE(all.equal(x, rep(x[1], length(x)))) # ugly
>>    
>>
>[1] TRUE
>
>Best,
>
>Vincent
>  
>