Re: Re: Bug: symbol recreates itself suddenly

*To*: mathgroup at smc.vnet.net*Subject*: [mg86829] Re: [mg86809] Re: Bug: symbol recreates itself suddenly*From*: DrMajorBob <drmajorbob at bigfoot.com>*Date*: Sat, 22 Mar 2008 00:54:42 -0500 (EST)*References*: <9457525.1205860522819.JavaMail.root@m08> <frqpu5$59m$1@smc.vnet.net> <20859482.1206092036607.JavaMail.root@m08>*Reply-to*: drmajorbob at longhorns.com

> Please don't ask why am I doing this. Too late, but I won't ask again, since I'm not, in fact, the least bit curious why you're doing it. If you DON'T do it, however, you won't have this problem. As for me, when I see a symbol that starts with a capital, I assume it's a built-in, created by Wolfram or a trustworthy 3rd party package. I don't change built-ins, and I never name my own variables with capital letters , so it's trivial to see which are mine and which are not, at a glance. That saves me a second here, a minute there... over time, it adds up. Maybe we're talking a whole HOUR by now. (Ha!) But that's OK, do it your way. (If you can.) > This is not forbidden according to > manual - and it worked in 4.0, 5.0, 5.2 versions. It should work in 6.0 > either. (Or it should be documented.) MANY things should be documented. ('Nuff said on THAT touchy topic.) Bobby On Fri, 21 Mar 2008 01:56:25 -0500, Severin Posta <severin at km1.fjfi.cvut.cz> wrote: > This is definitely NOT the correct answer. The correct answer is (should > be) > > "Symbol E not found." > > By all means this is really a bug. > > It has far-reaching consequences. Using symbol E afterwards can lead to > mistakes because Mathematica thinks (suddenly!) this is again Euler > constant, not general symbol. > > > > Please don't ask why am I doing this. This is not forbidden according to > manual - and it worked in 4.0, 5.0, 5.2 versions. It should work in 6.0 > either. (Or it should be documented.) > > Severin Posta > > "DrMajorBob" <drmajorbob at bigfoot.com> wrote in message > news:frqpu5$59m$1 at smc.vnet.net... >> "In[6]:= ?E >> >> E is the exponential constant e (base of natural logarithms), with \ >> numerical value \[TildeEqual]2.71828. >> >> >> (* THIS IS NOT CORRECT ANSWER *)" >> >> Oh yes, it certainly IS the correct answer. >> >> Why do you want to Remove built-in constants? (Regardless of whether it >> might or might not "work" to do so?) >> >> Bobby >> >> On Tue, 18 Mar 2008 04:50:49 -0500, Severin Posta >> >> <severin at km1.fjfi.cvut.cz> wrote: >> >>> It seems to me that after Remove[symbol] some times the symbol is >>> "recreated" without notice. Consider the following example. >>> >>> How to repeat: >>> >>> In[1]:= $Version >>> >>> Out[1]= "6.0 for Microsoft Windows (32-bit) (April 20, 2007)" >>> >>> In[2]:= Unprotect[E]; ClearAttributes[E, {Constant, Protected, >>> >>> ReadProtected}]; Remove[E]; >>> >>> In[4]:= ?E >>> >>> During evaluation of In[4]:= Information::notfound: Symbol E not >>> \ found. >> >>> >>> In[5]:= Solve[E == 2] >>> >>> Out[5]= {{Global`E -> 2}} >>> >>> (* ?! *) >>> >>> In[6]:= ?E >>> >>> E is the exponential constant e (base of natural logarithms), with \ >>> numerical value \[TildeEqual]2.71828. >> >>> >>> (* THIS IS NOT CORRECT ANSWER *) >>> >>> >>> >>> Severin Posta >>> >>> >>> >>> >>> >>> >> >> >> >> -- >> >> DrMajorBob at longhorns.com >> > > > > -- = DrMajorBob at longhorns.com