augmentablefeaturevector.java

常用机器学习算法,java编写源代码,内含常用分类算法,包括说明文档

					ret += values[i] * v.valueAtLocation(indices[vl]);
			}
		}
		return ret;
	}

	public final double dotProduct (AugmentableFeatureVector v) {
		if (indices != null && size-1 != maxSortedIndex)
			sortIndices();
		if (v.indices != null && v.size-1 != v.maxSortedIndex)
			v.sortIndices();
		double ret = 0;
		int vl = 0;
		int vnl = v.size;
		if (values == null) {
			if (v.values == null) {
				for (int i = 0; i < size; i++) {
					while (vl < vnl && v.indices[vl] < indices[i])
						vl++;
					if (vl < vnl && v.indices[vl] == indices[i])
						ret += 1.0;
				}
			} else {
				for (int i = 0; i < size; i++) {
					while (vl < vnl && v.indices[vl] < indices[i])
						vl++;
					if (vl < vnl && v.indices[vl] == indices[i])
						ret += v.values[vl];
				}
			}
		} else if (indices == null) {
			for (int i = 0; i < vnl; i++) {
				int index = v.indexAtLocation(i);
				if (index < size)
					ret += v.valueAtLocation(i) * values[index];
			}
		} else {
			if (v.values == null) {
				for (int i = 0; i < size; i++) {
					while (vl < vnl && v.indices[vl] < indices[i])
						vl++;
					if (vl < vnl && v.indices[vl] == indices[i])
						ret += values[i];
				}
			} else {
				for (int i = 0; i < size; i++) {
					while (vl < vnl && v.indices[vl] < indices[i])
						vl++;
					if (vl < vnl && v.indices[vl] == indices[i])
						ret += values[i] * v.values[vl];
				}
			}
		}
		return ret;
	}

	public void plusEquals (AugmentableFeatureVector v, double factor) {
		if (indices != null && size-1 != maxSortedIndex)
			sortIndices();
		if (v.indices != null && v.size-1 != v.maxSortedIndex)
			v.sortIndices();
		int vl = 0;
		int vnl = v.size;
		assert (values != null);
		if (indices == null) {
			if (v.indices == null) {
				vnl = Math.min (vnl, size);
				for (int i = 0; i < vnl; i++)
					values[i] += v.values[i];
			} else {
				// v.indices != null
				for (int i = 0; i < vnl; i++) {
					int index = v.indices[i];
					if (index < values.length) {
						values[index] += v.values[i] * factor;
						if (index >= size)
							size = index+1;
					}
				}
			}
		} else {
			// indices != null
			if (v.indices == null) {
				for (int i = 0; i < size; i++) {
					if (indices[i] < vnl)
						values[i] += v.values[indices[i]];
					// xxx We should check to see if there were more
					// higher indices in "v" that didn't get added!
				}
			} else {
				// v.indices != null
				if (v.values == null) {
					// v.indices != null && v.values == null
					for (int i = 0; i < size; i++) {
						while (vl < vnl && v.indices[vl] < indices[i])
							vl++;
						if (vl < vnl && v.indices[vl] == indices[i]) 
							values[i] += factor;
						// xxx We should check to see if there were more
						// higher indices in "v" that didn't get added!
					}
				} else {
					// v.indices != null && v.values != null
					for (int i = 0; i < size; i++) {
						while (vl < vnl && v.indices[vl] < indices[i])
							vl++;
						if (vl < vnl && v.indices[vl] == indices[i]) 
							values[i] += v.values[vl] * factor;
						// xxx We should check to see if there were more
						// higher indices in "v" that didn't get added!
					}
				}
			}
		}
	}

	// But only adds to those entries that have "locations" (i.e. are already non-zero)
	public void plusEquals (SparseVector v, double factor) {
		if (v instanceof AugmentableFeatureVector) {
			plusEquals ((AugmentableFeatureVector)v, factor);
			return;
		}
		//assert (false) : v.getClass().getName(); // This code needs to be checked!
		if (indices != null && size-1 != maxSortedIndex)
			sortIndices();
		int vl = 0;
		assert (values != null);
		if (indices == null) {
			if (v.indices == null) {
				// indices == null && v.indices == null (&& v.values != null)
				int s = Math.min (size, v.values.length);
				for (int i = 0; i < s; i++)
					values[i] += v.values[i] * factor;
				// xxx We aren't adding in values with indices higher than "this.size"!
			} else {
				// indices == null && v.indices != null
				if (v.values == null) {
					// indices == null && v.indices != null && v.values == null
					for (int i = 0; i < v.indices.length; i++) {
						int index = v.indices[i];
						if (index < size)
							values[index] += factor;
					}
					// xxx We aren't adding in values with indices higher than "size"!
				} else {
					// indices == null && v.indices != null && v.values != null
					for (int i = 0; i < v.indices.length; i++) {
						int index = v.indices[i];
						if (index < size)
							values[index] += v.values[i] * factor;
						// xxx We aren't adding in values with indices higher than "size"!
					}
				}
			}
		} else {
			// indices != null
			if (v.indices == null) {
				// indices != null && v.indices == null (&& v.values != null)
				for (int i = 0; i < size; i++)
					if (indices[i] < v.values.length)
						values[i] += v.values[indices[i]] * factor;
				// xxx We aren't adding in values with indices higher than "size"!
			} else {
				// indices != null && v.indices != null
				int vnl = v.indices.length;
				if (v.values == null) {
					// indices != null && v.indices != null && v.values == null
					for (int i = 0; i < size; i++) {
						while (vl < vnl && v.indices[vl] < indices[i])
							vl++;
						if (vl < vnl && v.indices[vl] == indices[i]) 
							values[i] += v.values[vl] * factor;
						// xxx We should check to see if there were more
						// higher indices in "v" that didn't get added!
					}
				} else {
					// indices != null && v.indices != null && v.values != null
					for (int i = 0; i < size; i++) {
						while (vl < vnl && v.indices[vl] < indices[i])
							vl++;
						if (vl < vnl && v.indices[vl] == indices[i]) 
							values[i] += v.values[vl] * factor;
						// xxx We should check to see if there were more
						// higher indices in "v" that didn't get added!
					}
				}
			}
		}
	}

	public void plusEquals (SparseVector v) {
		plusEquals (v, 1.0);
	}
	
	public void setAll (double v)
	{
		assert (values != null);
		for (int i = 0; i < values.length; i++)
			values[i] = v;
	}
	
	public double oneNorm () {
		if (size-1 != maxSortedIndex)
			sortIndices();
		double ret = 0;
		if (values == null)
			return size;
		for (int i = 0; i < size; i++)
			ret += values[i];
		return ret;
	}
	
	public double twoNorm () {
		if (size-1 != maxSortedIndex)
			sortIndices();
		double ret = 0;
		if (values == null)
			return Math.sqrt (size);
		for (int i = 0; i < size; i++)
			ret += values[i] * values[i];
		return Math.sqrt (ret);
	}
	
	public double infinityNorm () {
		if (size-1 != maxSortedIndex)
			sortIndices();
		if (values == null)
			return 1.0;
		double max = Double.NEGATIVE_INFINITY;
		for (int i = 0; i < size; i++)
			if (Math.abs(values[i]) > max)
				max = Math.abs(values[i]);
		return max;
	}		

	public void print() {
		//System.out.println ("ASV size="+size+" dict.size="+dictionary.size()+" values.length="+values.length+" indices.length="+indices.length);
		if (size-1 != maxSortedIndex)
			sortIndices();
		super.print();
	}

	
	protected void sortIndices ()
	{
		//System.out.println ("AFV sortIndices size="+size+" maxSortedIndex="+maxSortedIndex);
		if (indices == null)
			return;
		int numDuplicates = 0;
		// Just BubbleSort; this is efficient when already mostly sorted.
		// Note that we BubbleSort from the the end forward; this is most efficient
		//  when we have added a few additional items to the end of a previously sorted list.
		//  Note that we remember the highest index that was already sorted as "maxSortedIndex".
		// Note that maxSortedIndex may be -1 here, so the first time through the outer loop
		// just falls through immediately when the termination condition of the inner loop is met.
		for (int i = maxSortedIndex+1; i < size; i++) {
			//System.out.print ("fori="+i+"maxi="+maxSortedIndex+' ');
			boolean iIsDuplicate = false;
			for (int j = i; j > 0; j--) {
				//System.out.print ("i,j="+i+','+j+' ');
				if (indices[j] == indices[j-1]) {
					if (iIsDuplicate == false) {
						numDuplicates++;
						iIsDuplicate = true;
						//System.out.println (dictionary.lookupObject(indices[j]).toString()+" j="+j+" numDuplicates="+numDuplicates);
					}
				} else if (indices[j] < indices[j-1]) {
					// Swap both indices and values
					int f;
					f = indices[j];
					indices[j] = indices[j-1];
					indices[j-1] = f;
					if (values != null) {
						double v;
						v = values[j];
						values[j] = values[j-1];
						values[j-1] = v;
					}
				} else {
					break;
				}
			}
		}
		maxSortedIndex = size-1;
		if (numDuplicates > 0)
			removeDuplicates (numDuplicates);
	}
	
	// Argument zero is special value meaning that this function should count them.
	protected void removeDuplicates (int numDuplicates)
	{
		if (indices == null)
			return;
		//System.out.print ("AFV removeDuplicates ");
		//for (int i = 0; i < size; i++)
		//System.out.print (" " + dictionary.lookupObject(indices[i]) + "=" + indices[i]);
		//System.out.println (" numDuplicates="+numDuplicates);
		
		if (numDuplicates == 0)
			for (int i = 1; i < size; i++)
				if (indices[i-1] == indices[i])
					numDuplicates++;
		if (numDuplicates == 0)
			return;
		assert (indices.length - numDuplicates > 0)
			: "size="+size+" indices.length="+indices.length+" numDuplicates="+numDuplicates;
		int[] newIndices = new int[indices.length - numDuplicates];
		double[] newValues = values == null ? null : new double[indices.length - numDuplicates];
		newIndices[0] = indices[0];
		assert (indices.length >= size);
		for (int i = 0, j = 0; i < size-1; i++) {
			if (indices[i] == indices[i+1]) {
				if (values != null)
					newValues[j] += values[i];
			} else {
				newIndices[j] = indices[i];
				if (values != null)
					newValues[j] += values[i];
				j++;
			}
			if(i == size-2) {
				if(values != null)
					newValues[j] += values[i+1];
				newIndices[j] = indices[i+1];
			}
		}
		this.indices = newIndices;
		this.values = newValues;
		this.size -= numDuplicates;
	}

	// Serialization 
		
	private static final long serialVersionUID = 1;
	private static final int CURRENT_SERIAL_VERSION = 0;

	private void writeObject (ObjectOutputStream out) throws IOException {
		out.writeInt (CURRENT_SERIAL_VERSION);
		out.writeInt (size);
		out.writeInt (maxSortedIndex);
	}

	private void readObject (ObjectInputStream in) throws IOException, ClassNotFoundException {
		int version = in.readInt ();
		size = in.readInt();
		maxSortedIndex = in.readInt();
	}

}