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* fixed more bugs due to inexact nature of FPU

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This commit is contained in:
Jonas Maebe 2000-03-21 12:00:30 +00:00
parent 872031518d
commit 7e63fc9d28
1 changed files with 26 additions and 18 deletions
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42
rtl/inc/real2str.inc
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@ -129,6 +129,11 @@ var
dec(currPrec); dec(currPrec);
inc(spos); inc(spos);
temp[spos] := chr(intPart+ord('0')); temp[spos] := chr(intPart+ord('0'));
if temp[spos] > '9' then
begin
temp[spos] := chr(ord(temp[spos])-10);
roundStr(temp,spos-1);
end;
end; end;
corrVal := int(intPartStack[stackPtr]) * 10.0; corrVal := int(intPartStack[stackPtr]) * 10.0;
dec(stackPtr); dec(stackPtr);
@ -284,7 +289,7 @@ begin
if (spos = 2) and (d <> 0.0) then if (spos = 2) and (d <> 0.0) then
begin begin
{ take rounding errors into account } { take rounding errors into account }
while d < 1.0-roundCorr do while d < 0.1-roundCorr do
begin begin
d := d * 10.0; d := d * 10.0;
dec(correct); dec(correct);
@ -294,9 +299,7 @@ begin
if f >= 0 then if f >= 0 then
dec(currPrec); dec(currPrec);
end; end;
{ we decreased currPrec once too much } dec(correct);
if f >= 0 then
inc(currPrec);
end; end;
{ current length of the output string in endPos } { current length of the output string in endPos }
endPos := spos; endPos := spos;
@ -304,30 +307,32 @@ begin
if (currPrec >= 0) then if (currPrec >= 0) then
begin begin
if (currPrec > 0) then if (currPrec > 0) then
{ do some preliminary rounding (necessary, just like the } { round }
{ rounding afterwards) }
begin begin
corrVal := 0.5; corrVal := 0.5;
for fracCount := 1 to currPrec do for fracCount := 1 to currPrec do
corrVal := corrVal / 10.0; corrVal := corrVal / 10.0;
if d > corrVal then if d > corrVal then
d := d + corrVal; d := d + corrVal;
if int(d) = 1 then
begin
roundStr(temp,spos);
d := frac(d);
end;
end; end;
{ 0.0 < d < 1.0 if we didn't round of earlier, otherwise 1 < d < 10 }
if d < 1.0-roundCorr then
corrVal := frac(d) * 10
else corrVal := d;
{ calculate the necessary fractional digits } { calculate the necessary fractional digits }
for fracCount := 1 to currPrec do for fracCount := 1 to currPrec do
begin begin
d := frac(d) * 10.0;
inc(spos); inc(spos);
temp[spos] := chr(trunc(corrVal)+ord('0')); temp[spos] := chr(trunc(d)+ord('0'));
corrVal := frac(corrVal)*10.0; if temp[spos] > '9' then
{ possible because trunc and the "*10.0" aren't exact :( }
begin
temp[spos] := chr(ord(temp[spos]) - 10);
roundStr(temp,spos-1);
end;
end; end;
{ round off. We left a zero at the start, so we can't underflow }
{ to the length byte }
if (corrVal-5.0 > roundCorr) then
roundStr(temp,spos);
{ new length of string } { new length of string }
endPos := spos; endPos := spos;
end; end;
@ -388,7 +393,10 @@ end;
{ {
$Log$ $Log$
Revision 1.28 2000-03-17 20:20:33 jonas Revision 1.29 2000-03-21 12:00:30 jonas
* fixed more bugs due to inexact nature of FPU
Revision 1.28 2000/03/17 20:20:33 jonas
* fixed rounding bugs with certain formatting parameters in str_real * fixed rounding bugs with certain formatting parameters in str_real
* fixed tbs0218 so it compares both results only until max precision * fixed tbs0218 so it compares both results only until max precision