Java Maths.almostEquals方法代码示例

import cc.mallet.util.Maths; //导入方法依赖的package包/类
protected void splitTree(C45.Node node, int depth)
{
	// Stop growing the tree when any of the following is true:
	//   1.  We care about tree depth and maximum depth is reached
	//   2.  The entropy of the node is too small (i.e., all 
	//       instances belong to the same class)
	//   3.  The gain ratio of the best split available is too small
	if (m_depthLimited && depth == m_maxDepth) {
		logger.info("Splitting stopped: maximum depth reached (" + m_maxDepth + ")");
		return;
	}       
	else if (Maths.almostEquals(node.getGainRatio().getBaseEntropy(), 0)) {
		logger.info("Splitting stopped: entropy of node too small (" + node.getGainRatio().getBaseEntropy() + ")");
		return;
	}
	else if (Maths.almostEquals(node.getGainRatio().getMaxValue(), 0)) {
		logger.info("Splitting stopped: node has insignificant gain ratio (" + node.getGainRatio().getMaxValue() + ")");
		return;
	}
	logger.info("Splitting feature \""+node.getSplitFeature()
			+"\" at threshold=" + node.getGainRatio().getMaxValuedThreshold() 
			+ " gain ratio="+node.getGainRatio().getMaxValue());
	node.split();
	splitTree(node.getLeftChild(), depth+1);
	splitTree(node.getRightChild(), depth+1);
}
 

import cc.mallet.util.Maths; //导入方法依赖的package包/类
protected void divideByInternal (DiscreteFactor ptl)
{
  int[] projection = largeIdxToSmall (ptl);
  int numLocs = probs.numLocations ();
  for (int singleLoc = 0; singleLoc < numLocs; singleLoc++) {
    int smallIdx = projection[singleLoc];
    double prev = this.probs.valueAtLocation (singleLoc);
    double newVal = ptl.value (smallIdx);
    double product = prev / newVal;
    /* by convention, let dividing by zero just return 0 */
    if (Maths.almostEquals (newVal, 0)) {
      product = 0;
    }
    this.probs.setValueAtLocation (singleLoc, product);
  }
  Flops.increment (numLocs);
}
 

import cc.mallet.util.Maths; //导入方法依赖的package包/类
public boolean almostEquals (ConstantMatrix m2) {
	if (getNumDimensions () != m2.getNumDimensions ()) {
		return false;
	}
	if (numLocations () != m2.numLocations ()) {
		return false;
	}
	int[] dims1 = new int [getNumDimensions ()];
	int[] dims2 = new int [getNumDimensions ()];
	getDimensions (dims1);
	m2.getDimensions (dims2);
	for (int i = 0; i < dims1.length; i++) {
		if (dims1 [i] != dims2 [i]) {
			return false;
		}
	}
	for (int i = 0; i < numLocations(); i++) {
		if (!Maths.almostEquals (valueAtLocation (i), m2.valueAtLocation (i))) {
			return false;
		}
	}
	return true;
}
 

import cc.mallet.util.Maths; //导入方法依赖的package包/类
public double computeCostAndPrune()
{
	double costS = getMDL();

	if (isLeaf())
		return costS + 1;

	double minCost1 = getLeftChild().computeCostAndPrune();
	double minCost2 = getRightChild().computeCostAndPrune();
	double costSplit = Math.log(m_gainRatio.getNumSplitPointsForBestFeature()) / GainRatio.log2;
	double minCostN = Math.min(costS+1, costSplit+1+minCost1+minCost2);

	if (Maths.almostEquals(minCostN, costS+1))
		m_leftChild = m_rightChild = null;

	return minCostN;
}
 

import cc.mallet.util.Maths; //导入方法依赖的package包/类
public void multiplyBy (Factor f)
{
  if (f instanceof ConstantFactor) {
    double val = f.value (new Assignment());
    // NormalFactor must be normalized right now...
    if (Maths.almostEquals (val, 1.0)) {
      return;  // ok, it's an identity factor
    }
  }

  throw new UnsupportedOperationException ("Can't multiply NormalFactor by "+f);
}
 

import cc.mallet.util.Maths; //导入方法依赖的package包/类
public void multiplyBy (Factor f)
{
  if (f instanceof ConstantFactor) {
    double val = f.value (new Assignment());
    // NormalFactor must be normalized right now...
    if (Maths.almostEquals (val, 1.0)) {
      return;  // ok, it's an identity factor
    }
  }

  throw new UnsupportedOperationException ("Can't multiply BetaFactor by "+f);
}
 

import cc.mallet.util.Maths; //导入方法依赖的package包/类
public void divideBy (Factor f)
{
  if (f instanceof ConstantFactor) {
    double val = f.value (new Assignment());
    // NormalFactor must be normalized right now...
    if (Maths.almostEquals (val, 1.0)) {
      return;  // ok, it's an identity factor
    }
  }

  throw new UnsupportedOperationException ("Can't divide BetaFactor by "+f);
}
 

import cc.mallet.util.Maths; //导入方法依赖的package包/类
public void divideBy (Factor f)
{
  if (f instanceof ConstantFactor) {
    double val = f.value (new Assignment());
    // NormalFactor must be normalized right now...
    if (Maths.almostEquals (val, 1.0)) {
      return;  // ok, it's an identity factor
    }
  }

  throw new UnsupportedOperationException ("Can't divide NormalFactor by "+f);
}
 

import cc.mallet.util.Maths; //导入方法依赖的package包/类
public Factor multiply (Factor other)
{
  // special handling of identity factor
  if (Maths.almostEquals (c, 1.0)) {
    return other.duplicate ();
  } else if (other instanceof ConstantFactor) {
    return new ConstantFactor (c * ((ConstantFactor)other).c);
  } else {
    return other.multiply (this);
  }
}
 

import cc.mallet.util.Maths; //导入方法依赖的package包/类
public boolean almostEquals (Factor p, double epsilon)
{
  return (p instanceof ConstantFactor && Maths.almostEquals (c, ((ConstantFactor)p).c, epsilon));
}
 

import cc.mallet.util.Maths; //导入方法依赖的package包/类
public Instance pipe (Instance carrier)
{
  Sequence data = (Sequence) carrier.getData ();
  Sequence target = (Sequence) carrier.getTarget ();

  if (data.size () != target.size ())
    throw new IllegalArgumentException ("Trying to print into SimpleTagger format, where data and target lengths do not match\n"
    +"data.length = "+data.size()+", target.length = "+target.size ());

  int N = data.size ();

  if (data instanceof TokenSequence) {
    throw new UnsupportedOperationException ("Not yet implemented.");
  } else if (data instanceof FeatureVectorSequence) {

    FeatureVectorSequence fvs = (FeatureVectorSequence) data;
    Alphabet dict = (fvs.size() > 0) ? fvs.getFeatureVector (0).getAlphabet () : null;

    for (int i = 0; i < N; i++) {
      Object label = target.get (i);
      writer.print (label);

      FeatureVector fv = fvs.getFeatureVector (i);
      for (int loc = 0; loc < fv.numLocations (); loc++) {
        writer.print (' ');
        String fname = dict.lookupObject (fv.indexAtLocation (loc)).toString ();
        double value = fv.valueAtLocation (loc);
        if (!Maths.almostEquals (value, 1.0)) {
          throw new IllegalArgumentException ("Printing to SimpleTagger format: FeatureVector not binary at time slice "+i+" fv:"+fv);
        }
        writer.print (fname);
      }
      writer.println ();
    }
  } else {
    throw new IllegalArgumentException ("Don't know how to print data of type "+data);
  }

  writer.println ();

  return carrier;
}