Dear Frank, Thank you for the quick response.
I am familiar with the tradeoffs between integers and doubles. However, I do not believe this answers my question. If you look at the help information for the as() function it says: "as(x, "numeric") uses the existing as.numeric function." But clearly the result is different in each case. If the help for as() is correct, then as(1:10, "numeric") should also return doubles, and the second argument is not ignored. Erik > On Feb 1, 2016, at 8:16 AM, Franklin Bretschneider <brets...@xs4all.nl> wrote: > > Dear Erik Wright, > > > Re: > >> Could someone please explain this R behavior to me: >> >>> typeof(as.numeric(1:10)) >> [1] "double" >>> typeof(as(1:10, "numeric")) >> [1] "integer" >> >> I expected "double" in both cases. In the help for the "as" function it >> says: >> >> "Methods are pre-defined for coercing any object to one of the basic >> datatypes. For example, as(x, "numeric") uses the existing as.numeric >> function." > > > This happens because 1:10 yields only integers, and so can be stored cheap, > whereas as.numeric() actually means: as.double. > The "numeric" in the second line is an unused argument. > > Best regards, > > Frank > --- > > > > > Franklin Bretschneider > Dept of Biology > Utrecht University > brets...@xs4all.nl > > > ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
