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authorLaurent Balland-Poirier <laurent.balland-poirier@laposte.net>2016-06-22 23:53:01 +0200
committerEike Rathke <erack@redhat.com>2016-07-04 22:54:39 +0000
commit051329101dc249535dd09eeb34caf1c21719064f (patch)
tree5e23665089ed0ae6a438f7a888e3d3b2f2fc797f
parent9f8e2065c42f1724ac7a24f1bb0531e8c954698a (diff)
tdf#99996 New algorithm for fraction
This new algorithm, based on continued fraction representation: - is smarter (165 lines schrinked in 31) - gives same results for 1 to 3 digits for divider - gives better results for more than 3 digits for divider - is faster: 1.5% for 1 digit, 5% for 2 digits, 20% for 3 digits, 70% for 4 digits See details in bug report In addition - removed uncessary fonctions: ImpGGT and ImpGGTRound - forced denominator do not required anymore calculation of nFrac and nDiv - replace sal_uLong with sal_uInt32 for time - replace sal_uLong with sal_uInt64 for fraction Change-Id: I9bf3a54a5284104718a53406f8784379fd19f6e6 Reviewed-on: https://gerrit.libreoffice.org/26621 Tested-by: Jenkins <ci@libreoffice.org> Reviewed-by: Eike Rathke <erack@redhat.com> Tested-by: Eike Rathke <erack@redhat.com>
-rw-r--r--include/svl/zformat.hxx3
-rw-r--r--svl/source/numbers/zformat.cxx273
2 files changed, 53 insertions, 223 deletions
diff --git a/include/svl/zformat.hxx b/include/svl/zformat.hxx
index b9c4101effb8..ab82bcc23313 100644
--- a/include/svl/zformat.hxx
+++ b/include/svl/zformat.hxx
@@ -555,9 +555,6 @@ private:
double& fLimit,
SvNumberformatLimitOps eOp);
- SVL_DLLPRIVATE sal_uLong ImpGGT(sal_uLong x, sal_uLong y);
- SVL_DLLPRIVATE sal_uLong ImpGGTRound(sal_uLong x, sal_uLong y);
-
// Helper function for number strings
// append string symbols, insert leading 0 or ' ', or ...
SVL_DLLPRIVATE bool ImpNumberFill( OUStringBuffer& sStr,
diff --git a/svl/source/numbers/zformat.cxx b/svl/source/numbers/zformat.cxx
index 8a028857e0c9..aea14d0e3a37 100644
--- a/svl/source/numbers/zformat.cxx
+++ b/svl/source/numbers/zformat.cxx
@@ -62,9 +62,7 @@ const double EXP_ABS_UPPER_BOUND = 1.0E15; // use exponential notation above th
} // namespace
-const double D_MAX_U_LONG = (double) 0xffffffff; // 4294967295.0
-const sal_uInt16 MAX_FRACTION_PREC = 3;
-const double D_EPS = 1.0E-2;
+const double D_MAX_U_INT32 = (double) 0xffffffff; // 4294967295.0
const double D_MAX_D_BY_100 = 1.7E306;
const double D_MIN_M_BY_1000 = 2.3E-305;
@@ -1941,44 +1939,6 @@ void SvNumberformat::GetOutputString(const OUString& sString,
OutString = sOutBuff.makeStringAndClear();
}
-sal_uLong SvNumberformat::ImpGGT(sal_uLong x, sal_uLong y)
-{
- if (y == 0)
- {
- return x;
- }
- else
- {
- sal_uLong z = x%y;
- while (z)
- {
- x = y;
- y = z;
- z = x%y;
- }
- return y;
- }
-}
-
-sal_uLong SvNumberformat::ImpGGTRound(sal_uLong x, sal_uLong y)
-{
- if (y == 0)
- {
- return x;
- }
- else
- {
- sal_uLong z = x%y;
- while ((double)z/(double)y > D_EPS)
- {
- x = y;
- y = z;
- z = x%y;
- }
- return y;
- }
-}
-
namespace {
void lcl_GetOutputStringScientific(double fNumber, sal_uInt16 nCharCount,
@@ -2435,7 +2395,7 @@ bool SvNumberformat::ImpGetFractionOutput(double fNumber,
const ImpSvNumberformatInfo& rInfo = NumFor[nIx].Info();
const sal_uInt16 nAnz = NumFor[nIx].GetCount();
OUStringBuffer sStr, sFrac, sDiv; // Strings, value for
- sal_uLong nFrac, nDiv; // Integral part
+ sal_uInt64 nFrac=0, nDiv=1; // Integral part
bool bSign = false; // Numerator and denominator
if (fNumber < 0)
@@ -2448,7 +2408,7 @@ bool SvNumberformat::ImpGetFractionOutput(double fNumber,
double fNum = floor(fNumber); // Integral part
fNumber -= fNum; // Fractional part
- if (fNum > D_MAX_U_LONG || rInfo.nCntExp > 9) // Too large
+ if (fNum > D_MAX_U_INT32 || rInfo.nCntExp > 9) // Too large
{
sBuff = rScan.GetErrorString();
return false;
@@ -2460,177 +2420,10 @@ bool SvNumberformat::ImpGetFractionOutput(double fNumber,
return false;
}
- sal_uLong nBasis = ((sal_uLong)floor( pow(10.0,rInfo.nCntExp))) - 1; // 9, 99, 999 ,...
- sal_uLong x0, y0, x1, y1;
-
- if (rInfo.nCntExp <= MAX_FRACTION_PREC)
- {
- bool bUpperHalf;
-
- if (fNumber > 0.5)
- {
- bUpperHalf = true;
- fNumber -= (fNumber - 0.5) * 2.0;
- }
- else
- {
- bUpperHalf = false;
- }
- // Find entry to Farey sequence:
- x0 = (sal_uLong) floor(fNumber*nBasis); // e.g.: 2/9 <= x < 3/9
- if (x0 == 0) // => x0 = 2
- {
- y0 = 1;
- x1 = 1;
- y1 = nBasis;
- }
- else if (x0 == (nBasis-1)/2) // (b-1)/2, 1/2
- { // is ok (nBasis is odd)
- y0 = nBasis;
- x1 = 1;
- y1 = 2;
- }
- else if (x0 == 1)
- {
- y0 = nBasis; // 1/n; 1/(n-1)
- x1 = 1;
- y1 = nBasis - 1;
- }
- else
- {
- y0 = nBasis; // e.g.: 2/9 2/8
- x1 = x0;
- y1 = nBasis - 1;
- double fUg = (double) x0 / (double) y0;
- double fOg = (double) x1 / (double) y1;
- sal_uLong nGgt = ImpGGT(y0, x0); // x0/y0 kuerzen
- x0 /= nGgt;
- y0 /= nGgt; // Nest:
- sal_uLong x2 = 0;
- sal_uLong y2 = 0;
- bool bStop = false;
- while (!bStop)
- {
-#ifdef __GNUC__
- // #i21648# GCC over-optimizes something resulting
- // in wrong fTest values throughout the loops.
- volatile
-#endif
- double fTest = (double)x1/(double)y1;
- while (!bStop)
- {
- while (fTest > fOg)
- {
- x1--;
- fTest = (double)x1/(double)y1;
- }
- while (fTest < fUg && y1 > 1)
- {
- y1--;
- fTest = (double)x1/(double)y1;
- }
- if (fTest <= fOg)
- {
- fOg = fTest;
- bStop = true;
- }
- else if (y1 == 1)
- {
- bStop = true;
- }
- } // of while
- nGgt = ImpGGT(y1, x1); // Shorten x1/y1
- x2 = x1 / nGgt;
- y2 = y1 / nGgt;
- if (x2*y0 - x0*y2 == 1 || y1 <= 1) // Test for x2/y2
- bStop = true; // Next Farey number
- else
- {
- y1--;
- bStop = false;
- }
- } // of while
- x1 = x2;
- y1 = y2;
- } // of else
-
- double fup, flow;
-
- flow = (double)x0/(double)y0;
- fup = (double)x1/(double)y1;
- while (fNumber > fup)
- {
- sal_uLong x2 = ((y0+nBasis)/y1)*x1 - x0; // Next Farey number
- sal_uLong y2 = ((y0+nBasis)/y1)*y1 - y0;
-
- x0 = x1;
- y0 = y1;
- x1 = x2;
- y1 = y2;
- flow = fup;
- fup = (double)x1/(double)y1;
- }
- if (fNumber - flow < fup - fNumber)
- {
- nFrac = x0;
- nDiv = y0;
- }
- else
- {
- nFrac = x1;
- nDiv = y1;
- }
- if (bUpperHalf) // Recover original
- {
- if (nFrac == 0 && nDiv == 1) // 1/1
- {
- fNum += 1.0;
- }
- else
- {
- nFrac = nDiv - nFrac;
- }
- }
- }
- else // Large denominator
- { // 0,1234->123/1000
- sal_uLong nGgt;
-
- nDiv = 10000000;
- nFrac = ((sal_uLong)floor(0.5 + fNumber * 10000000.0));
- nGgt = ImpGGT(nDiv, nFrac);
- if (nGgt > 1)
- {
- nDiv /= nGgt;
- nFrac /= nGgt;
- }
- if (nDiv > nBasis)
- {
- nGgt = ImpGGTRound(nDiv, nFrac);
- if (nGgt > 1)
- {
- nDiv /= nGgt;
- nFrac /= nGgt;
- }
- }
- if (nDiv > nBasis)
- {
- nDiv = nBasis;
- nFrac = ((sal_uLong)floor(0.5 + fNumber *
- pow(10.0,rInfo.nCntExp)));
- nGgt = ImpGGTRound(nDiv, nFrac);
- if (nGgt > 1)
- {
- nDiv /= nGgt;
- nFrac /= nGgt;
- }
- }
- }
-
if( sal_Int32 nForcedDiv = lcl_GetDenominatorString(rInfo, nAnz).toInt32() )
- {
- nDiv = (sal_uLong) nForcedDiv;
- nFrac = (sal_uLong)floor ( fNumber * nDiv );
+ { // Forced Denominator
+ nDiv = (sal_uInt64) nForcedDiv;
+ nFrac = (sal_uInt64)floor ( fNumber * nDiv );
double fFracNew = (double)nFrac / (double)nDiv;
double fFracNew1 = (double)(nFrac + 1) / (double)nDiv;
double fDiff = fNumber - fFracNew;
@@ -2644,17 +2437,57 @@ bool SvNumberformat::ImpGetFractionOutput(double fNumber,
fNum = fNum + 1.0;
}
}
+ else // Calculated Denominator
+ {
+ sal_uInt64 nBasis = ((sal_uInt64)floor( pow(10.0,rInfo.nCntExp))) - 1; // 9, 99, 999 ,...
+ sal_uInt64 nFracPrev = 1L, nDivPrev = 0, nFracNext, nDivNext, nPartialDenom;
+ double fRemainder = fNumber, fTemp;
+
+ // Use continued fraction representation of fNumber
+ // See https://en.wikipedia.org/wiki/Continued_fraction#Best_rational_approximations
+ while ( fRemainder > 0.0 )
+ {
+ fTemp = 1.0 / fRemainder; // 64bits precision required when fRemainder is very weak
+ nPartialDenom = (sal_uInt64) floor(fTemp); // due to floating point notation with double precision
+ fRemainder = fTemp - (double)nPartialDenom;
+ nDivNext = nPartialDenom * nDiv + nDivPrev;
+ if ( nDivNext <= nBasis ) // continue loop
+ {
+ nFracNext = nPartialDenom * nFrac + nFracPrev;
+ nFracPrev = nFrac;
+ nFrac = nFracNext;
+ nDivPrev = nDiv;
+ nDiv = nDivNext;
+ }
+ else // calculate collateral fraction and exit
+ {
+ sal_uInt64 nCollat = (nBasis - nDivPrev) / nDiv;
+ if ( 2 * nCollat >= nPartialDenom )
+ {
+ sal_uInt64 nFracTest = nCollat * nFrac + nFracPrev;
+ sal_uInt64 nDivTest = nCollat * nDiv + nDivPrev;
+ double fSign = ((double)nFrac > fNumber * (double)nDiv)?1.0:-1.0;
+ if ( fSign * ( double(nFrac * nDivTest + nDiv * nFracTest) - 2.0 * double(nDiv * nDivTest) * fNumber ) > 0.0 )
+ {
+ nFrac = nFracTest;
+ nDiv = nDivTest;
+ }
+ }
+ fRemainder = 0.0; // exit while loop
+ }
+ }
+ }
if (rInfo.nCntPre == 0) // Improper fraction
{
double fNum1 = fNum * (double)nDiv + (double)nFrac;
- if (fNum1 > D_MAX_U_LONG)
+ if (fNum1 > D_MAX_U_INT32)
{
sBuff = rScan.GetErrorString();
return false;
}
- nFrac = (sal_uLong) floor(fNum1);
+ nFrac = (sal_uInt64) floor(fNum1);
}
else if (fNum == 0.0 && nFrac != 0)
{
@@ -2794,12 +2627,12 @@ bool SvNumberformat::ImpGetTimeOutput(double fNumber,
{
bSign = false; // Not -00:00:00
}
- if( floor( fTime ) > D_MAX_U_LONG )
+ if( floor( fTime ) > D_MAX_U_INT32 )
{
sBuff = rScan.GetErrorString();
return false;
}
- sal_uLong nSeconds = (sal_uLong)floor( fTime );
+ sal_uInt32 nSeconds = (sal_uInt32)floor( fTime );
OUStringBuffer sSecStr( ::rtl::math::doubleToUString( fTime-nSeconds,
rtl_math_StringFormat_F, int(nCntPost), '.'));
@@ -2821,7 +2654,7 @@ bool SvNumberformat::ImpGetTimeOutput(double fNumber,
}
sal_Int32 nSecPos = 0; // For figure by figure processing
- sal_uLong nHour, nMin, nSec;
+ sal_uInt32 nHour, nMin, nSec;
if (!rInfo.bThousand) // No [] format
{
nHour = (nSeconds/3600) % 24;
@@ -3581,7 +3414,7 @@ bool SvNumberformat::ImpGetDateTimeOutput(double fNumber,
}
sal_Int16 nNatNum = NumFor[nIx].GetNatNum().GetNatNum();
- sal_uLong nSeconds = (sal_uLong)floor( fTime );
+ sal_uInt32 nSeconds = (sal_uInt32)floor( fTime );
OUStringBuffer sSecStr( ::rtl::math::doubleToUString( fTime-nSeconds,
rtl_math_StringFormat_F, int(nCntPost), '.'));
sSecStr.stripStart('0');
@@ -3602,7 +3435,7 @@ bool SvNumberformat::ImpGetDateTimeOutput(double fNumber,
}
sal_Int32 nSecPos = 0; // For figure by figure processing
- sal_uLong nHour, nMin, nSec;
+ sal_uInt32 nHour, nMin, nSec;
if (!rInfo.bThousand) // [] format
{
nHour = (nSeconds/3600) % 24;