int getMaxGain(int parent, int S, int values[LENGTH][LENGTH], int nvalues, int nattributes, att * test)
{
float max=0;
int maxAtt;
int i;
float gain;
for(i=-1; i>-nattributes; i--)
{
if(isUsed(i, test)==0)
{
gain=getGain(parent, S, i, values, nvalues, nattributes, test);
printf("Gain of %d and %d is %lf\n", S, i, gain);
if(gain>max)
{
max=gain;
maxAtt=i;
}
}
}
if (max==0)
{
int pos=positiveValues(0, S, values, nvalues, nattributes, test);
int neg=negativeValues(0, S, values, nvalues, nattributes, test);
if (pos>neg)
{
maxAtt=100;
}
else
{
maxAtt=101;
}
}
return maxAtt;
}
float getEntropy(int S, int attribute, int values[LENGTH][LENGTH], int nvalues, int nattributes, att * test)
{
float entropy;
int positive;
int negative;
attnode * curr;
curr=test->head;
while(curr!=NULL)
{
if(curr->equivalent==attribute)
{
break;
}
curr=curr->next;
}
if(S==0)
{
positive=positiveValues(S, attribute, values, nvalues, nattributes, test);
negative=negativeValues(S, attribute, values, nvalues, nattributes, test);
}
else
{
updatePosNeg(S, attribute, values, nvalues, nattributes, test);
positive=curr->positivetracker;
negative=curr->negativetracker;
}
float pos;
float neg;
float logpos;
float logneg;
int total;
total=positive+negative;
pos=(float)positive/total;
neg=(float)negative/total;
logpos=log2(pos);
logneg=log2(neg);
if(positive==0||negative==0)
{
entropy=0;
}
else if(positive==negative)
{
entropy=1;
}
else
{
entropy=(-pos*logpos)-(neg*logneg);
printf("entropy of %d wrt %d=-%d/%dlg%d/%d - %d/%dlg%d/%d=%lf\n", attribute, S, positive, total, positive, total, negative, total, negative, total, entropy);
}
//printf("%d %lf %lf\n", total, pos, neg);
//printf("\nanswer: %lf\n", entropy);
return entropy;
}
void PlotDataFileCreator::createPlottableDatafile(std::string filename, std::string preamble, int max, int min, long* data, int dataSize, bool commentNeg)
{
const int maxValue = max;
const int minValue = min;
const int latHitArraySize = maxValue + 1;
const long* plotValues = data;
int hits[latHitArraySize];
for(int i = 0; i < latHitArraySize; i++)
{
hits[i] = 0;
}
const int loopLength = dataSize;
for(int i = 0; i < loopLength; i++)
{
if(plotValues[i] >= 0)
{
hits[plotValues[i]]++;
}
}
std::ofstream fs;
fs.open(filename.c_str());
fs << preamble;
std::stringstream positiveValues;
for(int i = 0; i < latHitArraySize; i++)
{
positiveValues << std::setfill('0') << std::setw(6) << i << " \t" << std::setfill('0') << std::setw(6) << hits[i] << std::endl;
}
std::stringstream negativeValues("");
if(minValue < 0)
{
const int negHitArraySize = minValue*(-1) + 1;
if(commentNeg)
{
negativeValues << "# negative Values following" << std::endl;
}
int negHits[negHitArraySize];
for(int i = 0; i < negHitArraySize; i++)
{
negHits[i] = 0;
}
for(int i = 0; i < loopLength; i++)
{
if(plotValues[i] < 0)
{
negHits[plotValues[i] * (-1)]++;
}
}
for(int i = negHitArraySize-1; i > 0; i--)
{
if(commentNeg)
{
negativeValues << "#";
}
negativeValues << "-" << std::setfill('0') << std::setw(6) << i << " \t" << std::setfill('0') << std::setw(6) << negHits[i] << std::endl;
}
}
if(commentNeg)
{
fs << positiveValues.str();
fs << negativeValues.str();
} else {
fs << negativeValues.str();
fs << positiveValues.str();
}
fs << std::endl << "end" << std::endl;
fs.close();
}
float getGain(int parent, int S, int attribute, int values[LENGTH][LENGTH], int nvalues, int nattributes, att * test)
{
attnode * curr;
attnode * curr2;
float entropy;
float entropy2;
float sum=0;
int denominator;
//=positiveValues(S, S, values, nvalues, nattributes, test)+negativeValues(S, S, values, nvalues, nattributes, test);
int numerator;
float gain;
int positive;
int negative;
entropy=getEntropy(parent, S, values, nvalues, nattributes, test);
//printf("ooh yas %lf\n", entropy);
curr=test->head;
while(curr!=NULL)
{
if(curr->equivalent==S)
{
break;
}
curr=curr->next;
}
if(S==0)
{
positive=positiveValues(S, S, values, nvalues, nattributes, test);
negative=negativeValues(S, S, values, nvalues, nattributes, test);
}
else
{
updatePosNeg(parent, S, values, nvalues, nattributes, test);
positive=curr->positivetracker;
negative=curr->negativetracker;
}
denominator=positive+negative;
curr=test->head;
while(curr!=NULL)
{
if(curr->equivalent==attribute)
{
//printf("Found curr: %s %d %d %d\n", curr->attname, curr->x, curr->y, curr->equivalent);
break;
}
curr=curr->next;
}
curr2=curr->next;
while(curr2!=NULL)
{
if(curr2->y==curr->y)
{
//printf("Found curr2: %s %d %d %d\n", curr2->attname, curr2->x, curr2->y, curr2->equivalent);
entropy2=getEntropy(S, curr2->equivalent, values, nvalues, nattributes, test);
//printf("Entropy: %lf\n", entropy2);
if (entropy2!=0)
{
if(S==0)
{
positive=positiveValues(S, curr2->equivalent, values, nvalues, nattributes, test);
negative=negativeValues(S, curr2->equivalent, values, nvalues, nattributes, test);
}
else
{
updatePosNeg(S, curr2->equivalent, values, nvalues, nattributes, test);
positive=curr2->positivetracker;
negative=curr2->negativetracker;
}
numerator=positive+negative;
//positiveValues(S, curr2->equivalent, values, nvalues, nattributes, test)+negativeValues(S, curr2->equivalent, values, nvalues, nattributes, test);
//printf("Numerator: %d\n", numerator);
//printf("Denominator: %d\n", denominator);
sum+=(float)numerator/denominator*entropy2;
printf("Gain+=%d/%d * %lf\n", numerator, denominator, entropy2);
//printf("Sum ryt nao: %lf\n", sum);
}
}
curr2=curr2->next;
}
gain=entropy-sum;
printf("Gain: %lf\n", gain);
return gain;
}
