[fpc-pascal] Freepascal Floating Point Issue

[Mark Morgan Lloyd]

On 21/08/17 22:15, Ralf Quint wrote:
> On 8/21/2017 3:02 PM, James Richters wrote:> I am having an issue with a simple floating point application.  I am setting a variable to a specific value and immediately after I set it,  it is not exactly what I set it to.  Here's an example>>    Draw_GX_Min:=999.999;>    Writeln(Draw_GX_Min:3:30);>> The writeln results in 999.999000000000020000000000000000  >> Why is it not  999.999000000000000000000000000000  where did 0.00000000000002 come from?>Out of thin air... Well, kind of. Double floating point means 16 digitsof precision, so when you force a 30 digit precision output, anythingpast 16 digits is random garbage, at best...

And in any event, that's probably much more precision than the GPU is 
using to generate the final image :-)

-- 
Mark Morgan Lloyd
markMLl .AT. telemetry.co .DOT. uk

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