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#include "continuedfractions.h"
#include "vektor.h"
#include <stdio.h>
void doubleToFraction(double f, int &numerator, int &denominator, int maksIter)
{
bool changeSign=f<0;
if(changeSign)f*=-1;
if(f<0.000001 || maksIter<1)
{
numerator=0;
denominator=1;
}
else
{
double r=1/f;
int R=int(r);//truncates
r-=R;
int n2,d2;
doubleToFraction(r,n2,d2,maksIter-1);
/* 1/f-R=r=n2/d2; => 1/f=(n2+d2*R)/d2; => f=d2/(n2+d2*R); */
numerator=d2;
denominator=n2+d2*R;
if(changeSign)
numerator*=-1;
}
}
void doubleVectorToFractions(vector<double> v, vector<int> &numerators, int &denominator)
{
int n=v.size();
numerators=vector<int>(n);
denominator=1;
if(n==0)return;
for(int i=0;i<n;i++)
{
int num,den;
doubleToFraction(v[i],num,den);
if(den==0)goto error;
denominator=(((signed long long)den)*denominator)/gcdGFAN(denominator,den);
}
for(int i=0;i<n;i++)
{
int num,den;
doubleToFraction(v[i],num,den);
if(den!=0)
numerators[i]=num*(denominator/den);
else
numerators[i]=num;//if v[i] is large it can happen that we lift to 1/0. Then we just produce some random result.
}
return;
error:
for(int i=0;i<n;i++)numerators[i]=0;denominator=1;
}
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