<denker at iam.unibe.ch> wrote:
To: <squeak-dev at lists.squeakfoundation.org>

<snip>

> from preamble:
> 
> "Change Set: Complex
> Date: 16 July 2004
> Author: Matej Kosik
> 
> md: This is just a first stab at an implementation of Complex. This will
> definitly need improvements, but the base functionality is there.
>  -removed Matrix, fixed undef references
>  -added test class.
</snip>

After a quit test, I think that this is good work.
There is one method that should be reconsidered:
complex division.

Look at this example:

  | c1 c2 quotient |
  c1 := 2.0e252 + 3.0e70 i.
  c2 := c1.
  quotient := c1 / c2.

The result should be  1.0 + 0.0 i
but we get an arithmetic overflow. 

There are algorithms that can avoid arithmetic overflow.
These algorithms use scaling of operands. 

Attached you find a change set with two such algorithms
:
* an added method  #divideSecureBy: (required six divisions)
* an added method #divideFastAndSecureBy: (requires only three divisions)
* three additional tests for complex division.

Just my two eurocents

Greetings, Boris

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