From simon.urbanek at math.uni-augsburg.de  Thu Jul  1 19:28:20 2004
From: simon.urbanek at math.uni-augsburg.de (Simon Urbanek)
Date: Thu Jul  1 19:29:05 2004
Subject: [Rd] AS_NUMERIC and as.numeric - Could someone explain?
In-Reply-To: <40E38E8A.5080209@stat.wisc.edu>
References: <000701c45eb8$8e001520$82b98283@DH>
	<40E38E8A.5080209@stat.wisc.edu>
Message-ID: <0BE5C464-CB84-11D8-806A-000A959F327E@math.uni-augsburg.de>

On Jul 1, 2004, at 6:09 AM, Douglas Bates wrote:

> AS_NUMERIC in C more closely corresponds to as.double() in R
>
> All that as.numeric() in R does is assure that the result is of a 
> numeric mode.  It does not coerce integer variables to doubles.

Um... are you sure?? For the sake of lots of code I saw I hope you're 
wrong:

> Check, for example,
> str(as.numeric(1:100))

Yes:

 > str(as.double(1:10))
  num [1:10] 1 2 3 4 5 6 7 8 9 10
 > str(as.numeric(1:10))
  num [1:10] 1 2 3 4 5 6 7 8 9 10
 > str(1:10)
  int [1:10] 1 2 3 4 5 6 7 8 9 10

And moreover:

 > as.numeric
function (x, ...)
UseMethod("as.double")
<environment: namespace:base>

... admittedly I didn't answer the original question, but I suspect 
that the problem lies somewhere else ...

Simon


[Rd] AS_NUMERIC and as.numeric - Could someone explain?
Simon Urbanek