[samigo-team] Floating point numbers

[David Horwitz]

There's a another issue (fixable without replacing floats but still)

There are several places in the code where direct foat comparisons are made:

Float a =
Float b,

if (a.equals(b))

For instance to check if an answer has been updated etc. We could be getting extra updated because of slight differences in the float representation ...

D

On Thu, 2013-02-28 at 09:11 -0500, Sam Ottenhoff wrote:

But just curious, what is the advantage of this change? Is this for getting a more precise score? Like some 0.999 issue?


An instructor created a complex placement exam that used point scores in the millions, thousands, hundreds, etc. as a way of being able to quickly see points in various sections in the final score (example: 27005508.06 could be broken up to see that the student scores 06 on sec 1, 08, on sec 2, 55 on sec 3, 27 on sec 4).


So the reason why floating point numbers aren't used for money:


> create table floattest (z float);
> insert into floattest VALUES (2075808);
> select * from floattest;


The result: 2075810


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