On Thu, Apr 07, 2005 at 11:58:48AM -0500, Earl F. Glynn wrote: > "Duncan Murdoch" <[EMAIL PROTECTED]> wrote in message > news:[EMAIL PROTECTED] > > > Seems to me the conversion from hex to decimal should be system > independent > > > (and makes working with colors much more convenient). Why isn't this > system > > > independent now? > > > > Presumably because nobody thought it was important enough to make it so. > > R isn't a low level system programming language, so why should it > > treat hex specially? > > 1) While generally I'd agree with your statement, manipulating colors is one > place the ability to convert to/from hex would be quite nice. > > > rgb(1,0,0.5) > [1] "#FF0080" > > rgb returns a hex string and then R makes manipulating this string somewhat > difficult.
I'd like to second this opinion. It just occasionally happens that data are available in some variant of hex format, and I've had the impression that getting such data into R is a bit less convenient than it could be. > One might want to use such color values to convert to a > different color space, perform some sort of manipulation in that other color > space, and then convert back to rgb. > > 2) I would think that one of R's mathematical abilities would be to provide > a way to convert from any base to base 10, and from base 10 to any base. I > haven't found this general math tool yet in R. Working with base-16 (or > even base 2 sometimes) could be done with such a general math tool. In fact, the ANSI C function strtol already provides conversion to any base between 2 and 36, so R's mathematical capabilities don't even need to be invoked here. An R function strtol(x, base), x being a character variable and base an integer between 2 and 36, would probably add a bit of convenience. I've never programmed that, though -- seems that I'm one of those to whom this hasn't been important enough. If it is done some day, I'd favour the strtol function over having as.numeric interpret the (rather C-ish) 0x prefix. I wasn't aware that this currently works on some platforms (and I'm glad it doesn't interpret the 0 prefix for octal, as C does, making 007 legal and 008 not. ;-) ) Best regards, Jan -- +- Jan T. Kim -------------------------------------------------------+ | *NEW* email: [EMAIL PROTECTED] | | *NEW* WWW: http://www.cmp.uea.ac.uk/people/jtk | *-----=< hierarchical systems are for files, not for humans >=-----* ______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
