Re: floating point conversions

[Mark Lusti <mark.lusti@bluewin.ch>]

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What about type conversion. I tried lately to calculate the floor after a
floating point calculation. I was quite surprised about the result.

result : integer;
fval : float;
  ...
for i in 1..10 loop
   fval := float(2 * i + 1);

  result := integer( fval / 2.0 - 0.5);
  put(result);
  put_line("");
end loop;

fval ->  3, 5, .. 21

expected result
1, 2, 3, 4, 5, 6, 7, 8, 9, 10

on the SUN I got the correct result but on the target (SVME160) the result was:
0, 2, 2, 4, 4, 6, 6, 8, 8, 10

Is this a bug? Or I'm I doing something wrong?
I found in ANSI/MIL-STD1815A under 4.6 Type Conversion
[...]
(a) Numeric types
 [...] The conversion of a real value to an integer type rounds to the nearest
integer; if the operand is halfway between two integers (within the accuracy of
the real subtype) rounding may be either up or down.

Shouldn't "either" mean one or the other?

Does anyone have a workaround without adding some EPSILON?

Thanx

mark






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