hex format
On Thu, Apr 07, 2005 at 11:58:48AM -0500, Earl F. Glynn wrote:
"Duncan Murdoch" <murdoch at stats.uwo.ca> wrote in message news:42555459.6040106 at stats.uwo.ca...
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: jtk at cmp.uea.ac.uk | | *NEW* WWW: http://www.cmp.uea.ac.uk/people/jtk | *-----=< hierarchical systems are for files, not for humans >=-----*