[R] names function not working at the 2nd place in a program

[MacQueen, Don]

I rather suspect you don't understand what it means to name an array.
Consider this example:

> myvar <- 1:4> myvar
[1] 1 2 3 4
> names(myvar)
NULL
> names(myvar) <- letters[1:4]
> myvar
a b c d 
1 2 3 4 
> names(myvar)
[1] "a" "b" "c" "d"
> as.numeric(names(myvar))
[1] NA NA NA NA
Warning message:
NAs introduced by coercion



For sure, 
  as.numeric(names(myVar1))
does not name the array.

-Don

-- 
Don MacQueen

Lawrence Livermore National Laboratory
7000 East Ave., L-627
Livermore, CA 94550
925-423-1062





On 7/26/12 2:19 PM, "zz" <czhang at uams.edu> wrote:

>Hello,
>
>I am using names function to name an array.
>It works first time when I use *as.numeric(names(myVar1)*
>However, at a place later, when I tried to use a very similar line of code
>*as.numeric(names(myVar2)*, it always returned 'numeric(0)' (or if I only
>type 'names(myVar2), it gave me NULL'.
>
>Both myVar1 and myVar2 are type of integer.  The only difference that I
>can
>tell is where the names function are called in my code.
>
>Does anyone have an idea what may cause the problem?
>
>Thanks in advance.
>
>
>
>--
>View this message in context:
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>in-a-program-tp4638004.html
>Sent from the R help mailing list archive at Nabble.com.
>
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