Thanks, Jim. While that is still in hex, I find I can get the binary
represntation using Gabor's gsubfn() function, provided the A-F isw
changed to a-f in setting up his 'binary.digits', and the output is
explicitly cast to character:
gsubfn("[0-9a-f]", binary.digits,
as.character(writeBin(pi,raw(),endian='big')
Ted.
On 17-May-09 20:04:58, jim holtman wrote:
> Are you looking for how the floating point is represented in the
> IEEE-754
> format? If so, you can use writeBin:
>
>> writeBin(pi,raw(),endian='big')
> [1] 40 09 21 fb 54 44 2d 18
>
>
> On Sun, May 17, 2009 at 1:23 PM, Ted Harding
> <ted.hard...@manchester.ac.uk>wrote:
>
>> I am interested in studying the binary representation of numerics
>> (doubles) in R, so am looking for possibilities of output of the
>> internal binary representations. sprintf() with format "a" or "A"
>> is halfway there:
>>
>> sprintf("%A",pi)
>> # [1] "0X1.921FB54442D18P+1"
>>
>> but it is in hex.
>>
>> The following illustrate the sort of thing I want:
>>
>> 1.1001 0010 0001 1111 1011 0101 0100 0100 0100 0010 1101 0001 1000
>> times 2
>>
>> 11.0010 0100 0011 1111 0110 1010 1000 1000 1000 0101 1010 0011 000
>>
>> 0.1100 1001 0000 1111 1101 1010 1010 0010 0010 0001 0110 1000 1100 0
>> times 4
>>
>> (without the spaces -- only put in above for clarity).
>>
>> While I could take the original output "0X1.921FB54442D18P+1" from
>> sprintf() and parse it out into binary using gsub() or the like,
>> of submit it to say an 'awk' script via an external file, this would
>> be a tedious business!
>>
>> Is there some function already in R which outputs the bits in the
>> binary representation directly?
>>
>> I see that Dabid Hinds asked a similar question on 17 Aug 2005:
>> "Raw data type transformations"
>>
>> http://finzi.psych.upenn.edu/R/Rhelp02/archive/59900.html
>>
>> (without, apparently, getting any response -- at any rate within
>> the following 3 months).
>>
>> With thanks for any suggestions,
>> Ted.
>>
>> --------------------------------------------------------------------
>> E-Mail: (Ted Harding) <ted.hard...@manchester.ac.uk>
>> Fax-to-email: +44 (0)870 094 0861
>> Date: 17-May-09 Time: 18:23:49
>> ------------------------------ XFMail ------------------------------
>>
>> ______________________________________________
>> R-help@r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide
>> http://www.R-project.org/posting-guide.html<http://www.r-project.org/po
>> sting-guide.html>
>> and provide commented, minimal, self-contained, reproducible code.
>>
>
>
>
> --
> Jim Holtman
> Cincinnati, OH
> +1 513 646 9390
>
> What is the problem that you are trying to solve?
--------------------------------------------------------------------
E-Mail: (Ted Harding) <ted.hard...@manchester.ac.uk>
Fax-to-email: +44 (0)870 094 0861
Date: 17-May-09 Time: 22:06:59
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