[Arjen Markus] (10 august 2004) "Real" numbers on computers can cause a lot of agony because they are implemented (most of the time) using binary rather than decimal arithmetic. Thus "obvious" computations like:

   0.1 + 0.1 == 0.2 

fail on most computer systems. There are many ways to solve these problems, though they almost always mean that you need another package or library than the default one - for instance arbitrary precision arithmetic packages.

An important class of applications where these problems are really annoying is that of financial computations. I am no expert in this field, but here is my thought:
''Why not use'' '''fixed-point arithmetic''' ''?'' 

The range for the numbers one deals with is fairly limited, the precision is too, but you do need "decimally" predictable results. 

I have an implementation of the basic arithmetical operations in mind that should be easy to use. It is Tcl only, will not imply too much overhead as most will be done using integer computations and ought to be flexible enough for most such applications. I have not coded it yet, just thought it over and I want to use this Wiki page to see if there is any interest in it ...

----
[[
[Category Mathematics]
]]