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Re: Re: Re: Re: Newly Released Mathematica 5.1 Delivers Unmatched Performance for Handling Data

They were warned, they did it anyway, and it broke their own code.

The word "comeuppance" springs to mind.


On Wed, 24 Nov 2004 02:32:19 -0500 (EST), David Park <djmp at> wrote:

> John,
> Your idea about non-conflicting color names seems good. Also there should be
> a unit Degree and a different name for the numerical constant.
> The specific problem here though is different.
> Previously, the package Graphics`Colors` contained a set of named colors.
> These colors were all uniformly represented in that they were all RGBColors.
> That is, they all had the same Head. This uniformity of representation was
> useful and I am certain that it plays a role in a lot of user code.
> In Version 5.1 the WRI developers have moved a few of the colors from the
> Graphics`Colors` package to the kernel. (I think this is a mistake because I
> am for similar things being treated uniformly. They should either move all
> of the color names to the kernel or keep them together in the package. But
> that is not the specific issue here. But suppose they move Gold to the
> kernel, then your message isn't going to work.) In doing this, WRI also
> changed the representation of certain neutral colors such as Black, White
> and Gray from RGBColor to GrayLevel. I think this is a great mistake because
> it will break every algorithm that depends on all named colors having the
> same Head. I cannot think of a good reason for making this gratuitous
> change.
> I found out about this problem from a beta tester who was using the
> DrawGraphics package where it broke the ColorMix function. When he
> complained to Wolfram Support (I never understand why beta testers must work
> through Wolfram Support and don't have direct contacts to the developers!)
> he just received a bureaucratic reply that said they took the possibility of
> breaking old code into account (but do it anyway) and that I could just
> change my code since my package was not Wolfram associated. (I did, but now
> users of the package will have to stumble across the problem, wonder what is
> going on, then check my site and download the new version.)
> I wrote (for the very first time and probably the very last time) to Steven
> Wolfram about it. He never replied. I wrote to another top person and only
> received a short reply that there was a good reason, although I never found
> out what that reason was. So WRI received at least three messages about this
> problem well before the release of 5.1.
> Now it turns out that this change not only affects user code "not associated
> with Wolfram Research" but also breaks their own code. RasterArray requires
> all the colors in the array to have the same Head. By fracturing the
> representation of the named colors the user can no longer obtain expected
> behavior for RasterArray, and I suppose also for DensityGraphics (maybe
> someone could test that with a color function that uses named colors with
> Black, White or Gray).
> It reminds me of that old vaudville doctor joke: "Doctor, my code breaks
> when I use Gray." "Then don't use Gray!"  Use RGBColor[0.752907, 0.752907,
> 0.752907].
> If this kind of thinking portends what we may expect for the user interface
> for the 'graphics' Version, whenever it should appear, then I wouldn't be
> too hopeful.
> David Park
> djmp at
> From: John Jowett [mailto:John.Jowett at]
To: mathgroup at
> "Yasvir Tesiram" <tesiramy at> wrote in message
> news:cns1p1$e1j$1 at
>> G'day David,
>> Very curious. I just checked and indeed all works fine with 5.0 but Gray
>> isn't liked much in 5.1. Neither is Black, another color defined by
>> GrayLevel. Other colors defined by RGB seems to work fine though.
>> There probably is a good reason floating around somewhere.
> Hello,
>         Not having 5.1 yet, I don't know exactly what the problem is but one
> good reason might be that some of the colours in Graphics`Colors` have names
> that clash with other useful packages.  Because of this, I have long had a
> private version which loads with the following message:
> Graphics`Colors` - loading modified version of this standard package in
> which \
> the colors
> {Cobalt, Gold, Gray, Titanium, Zinc}
> have been renamed:
> {CobaltColor, GoldColor, GrayColor, TitaniumColor, ZincColor}
> to eliminate clashes with the standard packages
> Miscellaneous`ChemicalElements` and Miscellaneous`Units`.
> I'm not sure if this explains a problem with Black though.
> John Jowett

DrBob at

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