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From "J.Pietschmann" <j3322...@yahoo.de>
Subject Re: [math] Complex implementation
Date Thu, 16 Oct 2003 21:19:01 GMT
Mark R. Diggory wrote:
> Not to suggest I'm not for creating a Complex class, I just know we have 
> issues.

Well, and *all* these issues have been discussed to death in the
C++ community before. While the FORTRAN folks were laughing.
Main points: in order to make a Complex class useful, you need
- a convenient notation
- acceptable performance, which basically means no temporary objects
- convenient mixing with other numerical datatypes

C++ ultimately got a solution heavily using operator overloading,
expression templates and half a zillion of auxillary classes.
The result is FORTRAN performance combined with an intuitive syntax,
and with the drawbacks of a compilation process taking forever plus
one day and nearly all available memory. And the library is
basically maintainable by demigods only. In what sense this is
better than making complex numbers a language built-in like in
FORTRAN still baffles me, but I digress.

Now to the point: Java currently doesn't have any of the mechanisms
which allowed the C++ crowds to meet ends. IOW: a pure Java
support for complex numbers will suck one way or another (probably
both). There is no way around the performance problem short of
providing a sophisticated preprocessor, thereby making complex
numbers a part of the language - which would solve the notation
and integration problem as well.

Matrices have the same problems as complex numbers, only worse. There
is a reason BLAS is only taught to people really needing it.

> Whate ever happened to the efforts at JCP to solve the complex 
> matrice conundrum?

How many projects would profit from convenient matrix and complex
number support? I'm not surprised there is not much pressure
to get something up and running.

J.Pietschmann


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