[R] How to spot/stop making the same mistake

[Jeff Newmiller]

I practically never construct vectors like your `t` so it isn't a problem. And since I make a habit of verifying the types of all vectors I am using in expressions, if it did come up I would notice.

On June 23, 2021 8:06:05 AM PDT, Phillips Rogfield <thebudget72 using gmail.com> wrote:
>I make the same mistake all over again.
>
>In particular, suppose we have:
>
>a = c(1,2,3,4,5)
>
>and a variable that equals 1 for the elements I want to select:
>
>t = c(1,1,1,0,0)
>
>To select the first 3 elements.
>
>The problem is that
>
>a[t]
>
>would repeat the first element 3 times .....
>
>I have to either convert `t` to boolean:
>
>a[t==1]
>
>Or use `which`
>
>a[which(t==1)]
>
>How can I "spot" this error?
>
>It often happens in long scripts.
>
>Do I have to check the type each time?
>
>Do you have any suggestions?
>
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-- 
Sent from my phone. Please excuse my brevity.