[R] Strange result when subsetting a data frame based on a character variable

[David L Carlson]

The conversion seems to be controlled by the scipen setting:

> options("scipen")
$scipen
[1] 0
> as.character(100000)
[1] "1e+05"
> options(scipen=5)
> as.character(100000)
[1] "100000"
> as.character(1000000)
[1] "1000000"
> as.character(10000000)
[1] "10000000"

-------------------------------------
David L Carlson
Department of Anthropology
Texas A&M University
College Station, TX 77840-4352


-----Original Message-----
From: R-help [mailto:r-help-bounces at r-project.org] On Behalf Of peter dalgaard
Sent: Tuesday, November 17, 2015 3:57 PM
To: Bert Gunter
Cc: r-help
Subject: Re: [R] Strange result when subsetting a data frame based on a character variable


> On 17 Nov 2015, at 20:37 , Bert Gunter <bgunter.4567 at gmail.com> wrote:
> 
>> 2 == "2"
> [1] TRUE
> 
> ?"=="  says:
> 
> "If the two arguments are atomic vectors of different types, one is
> coerced to the type of the other, the (decreasing) order of precedence
> being character, complex, numeric, integer, logical and raw."
> 
>> as.character(99999)
> [1] "99999"
>> as.character(100000)
> [1] "1e+05"
>> as.character(100000) == "100000"
> [1] FALSE
> 

Also notice that, for similar reasons

> 10 > "2"
[1] FALSE

(At least in most collations. I recently discovered that OSX Finder sorted 2dnorm.R between 02-Probability.toc and 03-Combinatorics-2x2.pdf.)	



-- 
Peter Dalgaard, Professor,
Center for Statistics, Copenhagen Business School
Solbjerg Plads 3, 2000 Frederiksberg, Denmark
Phone: (+45)38153501
Email: pd.mes at cbs.dk  Priv: PDalgd at gmail.com

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