[R] need help in if else condition

[Eric Berger]

Or even
> a <- 1:5
> [lots of other code]
> x <- ifelse( a < 3, 1, 2)

The point (in this example) is that you might have introduced a bug because
you forgot that 'a' is a vector.
Looking (in isolation) at the assignment to 'x' you believe it's going to
be a single number, either 1 or 2 (unless you know the "shape" of a).
I've been burned by such issues.


On Wed, Jul 10, 2019 at 4:42 PM Eric Berger <ericjberger using gmail.com> wrote:

> For example, can you predict what the following code will do?
> > a <- 1:5
> > b <- c(2,3)
> > ifelse( a < 3, 1, b)
>
>
> On Wed, Jul 10, 2019 at 4:34 PM José María Mateos <chema using rinzewind.org>
> wrote:
>
>> On Wed, Jul 10, 2019, at 04:39, Eric Berger wrote:
>> > 1. The ifelse() command is a bit tricky in R. Avoiding it is often a
>> good
>> > policy.
>>
>> You piqued my curiosity, can you elaborate a bit more on this?
>>
>> --
>> José María (Chema) Mateos || https://rinzewind.org
>>
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>

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