7.126 Bug in simplify(Dirac) in MapleV.4 and Maple V.5 (21.10.98)

7.126.1 Lev A. Melnikovsky

It seems I don’t understand pretty much. Either in Maths or in Maple. Here’s what I do (Version 4.00b, library patch level 2)

> Dirac(2*x+y); 
                                Dirac(2 x + y) 
 
> simplify(%); 
                              1/2 Dirac(2 x + y)
 

Could someone, please, help me? Is it a feature or a bug? Do I miss something? It seems I’m going to become crazy with it...

P.S. Look at `simplify/Dirac/expression`! It looks rather strange...

It is corrected with Maple 6. (U. Klein)

7.126.2 Robert Israel (27.10.98)

It’s a bug. At first I thought it was fixed in Release 5, but then I realized it was not: the bug may or may not occur, depending on whether Maple happens to look at the \(x\) or \(y\) variable first. If you try

> simplify(Dirac(2*x+3*y));
 

you’ll always get an incorrect answer, but sometimes it will have a factor 1/2 and sometimes 1/3.