Warning: condition has length > 1
On Sat, 8 Oct 2005, nawaf b wrote:
Hi - I was wondering if anyone came across a problem such as mine! I was trying to create a user-defined function, however, the results from calling the function are unexpected! When passing X parameter as a single value variable (x<-c(3)), everything works fine. However, when passing a parameter as a vector with multiple values (as the case in my code), the 'if condition' is only executed once! Here is my code:
x
[1] 0.3 1.0 0.7 22.0
myfunction<-function(x)
+ {
+ if (x>=1) 0
+ else x^2
+ }
myfunction(x)
[1] 0.09 1.00 0.49 484.00 Warning message: the condition has length > 1 and only the first element will be used in: if (x >= 1) 0 else x^2
Is there a way to overcome this issue? Can you please explain what modifications to the code I need to accommodate to make it work.
myfunction<-function(x)
+ ifelse(x>=1, 0, x^2)
x <- c(0.3, 1.0, 0.7, 22.0) myfunction(x)
[1] 0.09 0.00 0.49 0.00 ifelse() is vectorised, but if() only looks at the first element in x before deciding what to do - so if the condition is longer, the rest gets ignored.
Thanks, Nawaf
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