it = iterator();
while (it.hasNext()) {
final Entry e = it.next();
final int index = e.getIndex();
result.setEntry(index, e.getValue() + result.getEntry(index));
}
return result;
}
/**
* Add a value to each entry. Returns a new vector. Does not change instance data.
*
* @param d Value to be added to each entry.
* @return {@code this} + {@code d}.
*/
public RealVector mapAdd(double d) {
return copy().mapAddToSelf(d);
}
/**
* Add a value to each entry. The instance is changed in-place.
*
* @param d Value to be added to each entry.
* @return {@code this}.
*/
public RealVector mapAddToSelf(double d) {
if (d != 0) {
return mapToSelf(FunctionUtils.fix2ndArgument(new Add(), d));
}
return this;
}
/**
* Returns a (deep) copy of this vector.
*
* @return a vector copy.
*/
public abstract RealVector copy();
/**
* Compute the dot product of this vector with {@code v}.
*
* @param v Vector with which dot product should be computed
* @return the scalar dot product between this instance and {@code v}.
* @throws DimensionMismatchException if {@code v} is not the same size as {@code this} vector.
*/
public double dotProduct(RealVector v) throws DimensionMismatchException {
checkVectorDimensions(v);
double d = 0;
final int n = getDimension();
for (int i = 0; i < n; i++) {
d += getEntry(i) * v.getEntry(i);
}
return d;
}
/**
* Computes the cosine of the angle between this vector and the argument.
*
* @param v Vector.
* @return the cosine of the angle between this vector and {@code v}.
* @throws MathArithmeticException if {@code this} or {@code v} is the null vector
* @throws DimensionMismatchException if the dimensions of {@code this} and {@code v} do not
* match
*/
public double cosine(RealVector v) throws DimensionMismatchException, MathArithmeticException {
final double norm = getNorm();
final double vNorm = v.getNorm();
if (norm == 0 || vNorm == 0) {
throw new MathArithmeticException(LocalizedFormats.ZERO_NORM);
}
return dotProduct(v) / (norm * vNorm);
}
/**
* Element-by-element division.
*
* @param v Vector by which instance elements must be divided.
* @return a vector containing this[i] / v[i] for all i.
* @throws DimensionMismatchException if {@code v} is not the same size as {@code this} vector.
*/
public abstract RealVector ebeDivide(RealVector v) throws DimensionMismatchException;
/**
* Element-by-element multiplication.
*
* @param v Vector by which instance elements must be multiplied
* @return a vector containing this[i] * v[i] for all i.
* @throws DimensionMismatchException if {@code v} is not the same size as {@code this} vector.
*/
public abstract RealVector ebeMultiply(RealVector v) throws DimensionMismatchException;
/**
* Distance between two vectors.
*
* This method computes the distance consistent with the L2 norm, i.e. the square
* root of the sum of element differences, or Euclidean distance.
*
* @param v Vector to which distance is requested.
* @return the distance between two vectors.
* @throws DimensionMismatchException if {@code v} is not the same size as {@code this} vector.
* @see #getL1Distance(RealVector)
* @see #getLInfDistance(RealVector)
* @see #getNorm()
*/
public double getDistance(RealVector v) throws DimensionMismatchException {
checkVectorDimensions(v);
double d = 0;
Iterator it = iterator();
while (it.hasNext()) {
final Entry e = it.next();
final double diff = e.getValue() - v.getEntry(e.getIndex());
d += diff * diff;
}
return FastMath.sqrt(d);
}
/**
* Returns the L2 norm of the vector.
*
* The L2 norm is the root of the sum of the squared elements.
*
* @return the norm.
* @see #getL1Norm()
* @see #getLInfNorm()
* @see #getDistance(RealVector)
*/
public double getNorm() {
double sum = 0;
Iterator it = iterator();
while (it.hasNext()) {
final Entry e = it.next();
final double value = e.getValue();
sum += value * value;
}
return FastMath.sqrt(sum);
}
/**
* Returns the L1 norm of the vector.
*
* The L1 norm is the sum of the absolute values of the elements.
*
* @return the norm.
* @see #getNorm()
* @see #getLInfNorm()
* @see #getL1Distance(RealVector)
*/
public double getL1Norm() {
double norm = 0;
Iterator it = iterator();
while (it.hasNext()) {
final Entry e = it.next();
norm += FastMath.abs(e.getValue());
}
return norm;
}
/**
* Returns the L∞ norm of the vector.
*
* The L∞ norm is the max of the absolute values of the elements.
*
* @return the norm.
* @see #getNorm()
* @see #getL1Norm()
* @see #getLInfDistance(RealVector)
*/
public double getLInfNorm() {
double norm = 0;
Iterator it = iterator();
while (it.hasNext()) {
final Entry e = it.next();
norm = FastMath.max(norm, FastMath.abs(e.getValue()));
}
return norm;
}
/**
* Distance between two vectors.
*
* This method computes the distance consistent with L1 norm, i.e. the sum of the
* absolute values of the elements differences.
*
* @param v Vector to which distance is requested.
* @return the distance between two vectors.
* @throws DimensionMismatchException if {@code v} is not the same size as {@code this} vector.
*/
public double getL1Distance(RealVector v) throws DimensionMismatchException {
checkVectorDimensions(v);
double d = 0;
Iterator it = iterator();
while (it.hasNext()) {
final Entry e = it.next();
d += FastMath.abs(e.getValue() - v.getEntry(e.getIndex()));
}
return d;
}
/**
* Distance between two vectors.
*
* This method computes the distance consistent with L∞ norm, i.e. the max
* of the absolute values of element differences.
*
* @param v Vector to which distance is requested.
* @return the distance between two vectors.
* @throws DimensionMismatchException if {@code v} is not the same size as {@code this} vector.
* @see #getDistance(RealVector)
* @see #getL1Distance(RealVector)
* @see #getLInfNorm()
*/
public double getLInfDistance(RealVector v) throws DimensionMismatchException {
checkVectorDimensions(v);
double d = 0;
Iterator it = iterator();
while (it.hasNext()) {
final Entry e = it.next();
d = FastMath.max(FastMath.abs(e.getValue() - v.getEntry(e.getIndex())), d);
}
return d;
}
/**
* Get the index of the minimum entry.
*
* @return the index of the minimum entry or -1 if vector length is 0 or all entries are {@code
* NaN}.
*/
public int getMinIndex() {
int minIndex = -1;
double minValue = Double.POSITIVE_INFINITY;
Iterator iterator = iterator();
while (iterator.hasNext()) {
final Entry entry = iterator.next();
if (entry.getValue() <= minValue) {
minIndex = entry.getIndex();
minValue = entry.getValue();
}
}
return minIndex;
}
/**
* Get the value of the minimum entry.
*
* @return the value of the minimum entry or {@code NaN} if all entries are {@code NaN}.
*/
public double getMinValue() {
final int minIndex = getMinIndex();
return minIndex < 0 ? Double.NaN : getEntry(minIndex);
}
/**
* Get the index of the maximum entry.
*
* @return the index of the maximum entry or -1 if vector length is 0 or all entries are {@code
* NaN}
*/
public int getMaxIndex() {
int maxIndex = -1;
double maxValue = Double.NEGATIVE_INFINITY;
Iterator iterator = iterator();
while (iterator.hasNext()) {
final Entry entry = iterator.next();
if (entry.getValue() >= maxValue) {
maxIndex = entry.getIndex();
maxValue = entry.getValue();
}
}
return maxIndex;
}
/**
* Get the value of the maximum entry.
*
* @return the value of the maximum entry or {@code NaN} if all entries are {@code NaN}.
*/
public double getMaxValue() {
final int maxIndex = getMaxIndex();
return maxIndex < 0 ? Double.NaN : getEntry(maxIndex);
}
/**
* Multiply each entry by the argument. Returns a new vector. Does not change instance data.
*
* @param d Multiplication factor.
* @return {@code this} * {@code d}.
*/
public RealVector mapMultiply(double d) {
return copy().mapMultiplyToSelf(d);
}
/**
* Multiply each entry. The instance is changed in-place.
*
* @param d Multiplication factor.
* @return {@code this}.
*/
public RealVector mapMultiplyToSelf(double d) {
return mapToSelf(FunctionUtils.fix2ndArgument(new Multiply(), d));
}
/**
* Subtract a value from each entry. Returns a new vector. Does not change instance data.
*
* @param d Value to be subtracted.
* @return {@code this} - {@code d}.
*/
public RealVector mapSubtract(double d) {
return copy().mapSubtractToSelf(d);
}
/**
* Subtract a value from each entry. The instance is changed in-place.
*
* @param d Value to be subtracted.
* @return {@code this}.
*/
public RealVector mapSubtractToSelf(double d) {
return mapAddToSelf(-d);
}
/**
* Divide each entry by the argument. Returns a new vector. Does not change instance data.
*
* @param d Value to divide by.
* @return {@code this} / {@code d}.
*/
public RealVector mapDivide(double d) {
return copy().mapDivideToSelf(d);
}
/**
* Divide each entry by the argument. The instance is changed in-place.
*
* @param d Value to divide by.
* @return {@code this}.
*/
public RealVector mapDivideToSelf(double d) {
return mapToSelf(FunctionUtils.fix2ndArgument(new Divide(), d));
}
/**
* Compute the outer product.
*
* @param v Vector with which outer product should be computed.
* @return the matrix outer product between this instance and {@code v}.
*/
public RealMatrix outerProduct(RealVector v) {
final int m = this.getDimension();
final int n = v.getDimension();
final RealMatrix product;
if (v instanceof SparseRealVector || this instanceof SparseRealVector) {
product = new OpenMapRealMatrix(m, n);
} else {
product = new Array2DRowRealMatrix(m, n);
}
for (int i = 0; i < m; i++) {
for (int j = 0; j < n; j++) {
product.setEntry(i, j, this.getEntry(i) * v.getEntry(j));
}
}
return product;
}
/**
* Find the orthogonal projection of this vector onto another vector.
*
* @param v vector onto which instance must be projected.
* @return projection of the instance onto {@code v}.
* @throws DimensionMismatchException if {@code v} is not the same size as {@code this} vector.
* @throws MathArithmeticException if {@code this} or {@code v} is the null vector
*/
public RealVector projection(final RealVector v)
throws DimensionMismatchException, MathArithmeticException {
final double norm2 = v.dotProduct(v);
if (norm2 == 0.0) {
throw new MathArithmeticException(LocalizedFormats.ZERO_NORM);
}
return v.mapMultiply(dotProduct(v) / v.dotProduct(v));
}
/**
* Set all elements to a single value.
*
* @param value Single value to set for all elements.
*/
public void set(double value) {
Iterator it = iterator();
while (it.hasNext()) {
final Entry e = it.next();
e.setValue(value);
}
}
/**
* Convert the vector to an array of {@code double}s. The array is independent from this vector
* data: the elements are copied.
*
* @return an array containing a copy of the vector elements.
*/
public double[] toArray() {
int dim = getDimension();
double[] values = new double[dim];
for (int i = 0; i < dim; i++) {
values[i] = getEntry(i);
}
return values;
}
/**
* Creates a unit vector pointing in the direction of this vector. The instance is not changed
* by this method.
*
* @return a unit vector pointing in direction of this vector.
* @throws MathArithmeticException if the norm is zero.
*/
public RealVector unitVector() throws MathArithmeticException {
final double norm = getNorm();
if (norm == 0) {
throw new MathArithmeticException(LocalizedFormats.ZERO_NORM);
}
return mapDivide(norm);
}
/**
* Converts this vector into a unit vector. The instance itself is changed by this method.
*
* @throws MathArithmeticException if the norm is zero.
*/
public void unitize() throws MathArithmeticException {
final double norm = getNorm();
if (norm == 0) {
throw new MathArithmeticException(LocalizedFormats.ZERO_NORM);
}
mapDivideToSelf(getNorm());
}
/**
* Create a sparse iterator over the vector, which may omit some entries. The ommitted entries
* are either exact zeroes (for dense implementations) or are the entries which are not stored
* (for real sparse vectors). No guarantees are made about order of iteration.
*
* Note: derived classes are required to return an {@link Iterator} that returns non-null
* {@link Entry} objects as long as {@link Iterator#hasNext()} returns {@code true}.
*
* @return a sparse iterator.
*/
public Iterator sparseIterator() {
return new SparseEntryIterator();
}
/**
* Generic dense iterator. Iteration is in increasing order of the vector index.
*
* Note: derived classes are required to return an {@link Iterator} that returns non-null
* {@link Entry} objects as long as {@link Iterator#hasNext()} returns {@code true}.
*
* @return a dense iterator.
*/
public Iterator iterator() {
final int dim = getDimension();
return new Iterator() {
/** Current index. */
private int i = 0;
/** Current entry. */
private Entry e = new Entry();
/** {@inheritDoc} */
public boolean hasNext() {
return i < dim;
}
/** {@inheritDoc} */
public Entry next() {
if (i < dim) {
e.setIndex(i++);
return e;
} else {
throw new NoSuchElementException();
}
}
/**
* {@inheritDoc}
*
* @throws MathUnsupportedOperationException in all circumstances.
*/
public void remove() throws MathUnsupportedOperationException {
throw new MathUnsupportedOperationException();
}
};
}
/**
* Acts as if implemented as:
*
*
* return copy().mapToSelf(function);
*
*
* Returns a new vector. Does not change instance data.
*
* @param function Function to apply to each entry.
* @return a new vector.
*/
public RealVector map(UnivariateFunction function) {
return copy().mapToSelf(function);
}
/**
* Acts as if it is implemented as:
*
*
* Entry e = null;
* for(Iterator it = iterator(); it.hasNext(); e = it.next()) {
* e.setValue(function.value(e.getValue()));
* }
*
*
* Entries of this vector are modified in-place by this method.
*
* @param function Function to apply to each entry.
* @return a reference to this vector.
*/
public RealVector mapToSelf(UnivariateFunction function) {
Iterator it = iterator();
while (it.hasNext()) {
final Entry e = it.next();
e.setValue(function.value(e.getValue()));
}
return this;
}
/**
* Returns a new vector representing {@code a * this + b * y}, the linear combination of {@code
* this} and {@code y}. Returns a new vector. Does not change instance data.
*
* @param a Coefficient of {@code this}.
* @param b Coefficient of {@code y}.
* @param y Vector with which {@code this} is linearly combined.
* @return a vector containing {@code a * this[i] + b * y[i]} for all {@code i}.
* @throws DimensionMismatchException if {@code y} is not the same size as {@code this} vector.
*/
public RealVector combine(double a, double b, RealVector y) throws DimensionMismatchException {
return copy().combineToSelf(a, b, y);
}
/**
* Updates {@code this} with the linear combination of {@code this} and {@code y}.
*
* @param a Weight of {@code this}.
* @param b Weight of {@code y}.
* @param y Vector with which {@code this} is linearly combined.
* @return {@code this}, with components equal to {@code a * this[i] + b * y[i]} for all {@code
* i}.
* @throws DimensionMismatchException if {@code y} is not the same size as {@code this} vector.
*/
public RealVector combineToSelf(double a, double b, RealVector y)
throws DimensionMismatchException {
checkVectorDimensions(y);
for (int i = 0; i < getDimension(); i++) {
final double xi = getEntry(i);
final double yi = y.getEntry(i);
setEntry(i, a * xi + b * yi);
}
return this;
}
/**
* Visits (but does not alter) all entries of this vector in default order (increasing index).
*
* @param visitor the visitor to be used to process the entries of this vector
* @return the value returned by {@link RealVectorPreservingVisitor#end()} at the end of the
* walk
* @since 3.1
*/
public double walkInDefaultOrder(final RealVectorPreservingVisitor visitor) {
final int dim = getDimension();
visitor.start(dim, 0, dim - 1);
for (int i = 0; i < dim; i++) {
visitor.visit(i, getEntry(i));
}
return visitor.end();
}
/**
* Visits (but does not alter) some entries of this vector in default order (increasing index).
*
* @param visitor visitor to be used to process the entries of this vector
* @param start the index of the first entry to be visited
* @param end the index of the last entry to be visited (inclusive)
* @return the value returned by {@link RealVectorPreservingVisitor#end()} at the end of the
* walk
* @throws NumberIsTooSmallException if {@code end < start}.
* @throws OutOfRangeException if the indices are not valid.
* @since 3.1
*/
public double walkInDefaultOrder(
final RealVectorPreservingVisitor visitor, final int start, final int end)
throws NumberIsTooSmallException, OutOfRangeException {
checkIndices(start, end);
visitor.start(getDimension(), start, end);
for (int i = start; i <= end; i++) {
visitor.visit(i, getEntry(i));
}
return visitor.end();
}
/**
* Visits (but does not alter) all entries of this vector in optimized order. The order in which
* the entries are visited is selected so as to lead to the most efficient implementation; it
* might depend on the concrete implementation of this abstract class.
*
* @param visitor the visitor to be used to process the entries of this vector
* @return the value returned by {@link RealVectorPreservingVisitor#end()} at the end of the
* walk
* @since 3.1
*/
public double walkInOptimizedOrder(final RealVectorPreservingVisitor visitor) {
return walkInDefaultOrder(visitor);
}
/**
* Visits (but does not alter) some entries of this vector in optimized order. The order in
* which the entries are visited is selected so as to lead to the most efficient implementation;
* it might depend on the concrete implementation of this abstract class.
*
* @param visitor visitor to be used to process the entries of this vector
* @param start the index of the first entry to be visited
* @param end the index of the last entry to be visited (inclusive)
* @return the value returned by {@link RealVectorPreservingVisitor#end()} at the end of the
* walk
* @throws NumberIsTooSmallException if {@code end < start}.
* @throws OutOfRangeException if the indices are not valid.
* @since 3.1
*/
public double walkInOptimizedOrder(
final RealVectorPreservingVisitor visitor, final int start, final int end)
throws NumberIsTooSmallException, OutOfRangeException {
return walkInDefaultOrder(visitor, start, end);
}
/**
* Visits (and possibly alters) all entries of this vector in default order (increasing index).
*
* @param visitor the visitor to be used to process and modify the entries of this vector
* @return the value returned by {@link RealVectorChangingVisitor#end()} at the end of the walk
* @since 3.1
*/
public double walkInDefaultOrder(final RealVectorChangingVisitor visitor) {
final int dim = getDimension();
visitor.start(dim, 0, dim - 1);
for (int i = 0; i < dim; i++) {
setEntry(i, visitor.visit(i, getEntry(i)));
}
return visitor.end();
}
/**
* Visits (and possibly alters) some entries of this vector in default order (increasing index).
*
* @param visitor visitor to be used to process the entries of this vector
* @param start the index of the first entry to be visited
* @param end the index of the last entry to be visited (inclusive)
* @return the value returned by {@link RealVectorChangingVisitor#end()} at the end of the walk
* @throws NumberIsTooSmallException if {@code end < start}.
* @throws OutOfRangeException if the indices are not valid.
* @since 3.1
*/
public double walkInDefaultOrder(
final RealVectorChangingVisitor visitor, final int start, final int end)
throws NumberIsTooSmallException, OutOfRangeException {
checkIndices(start, end);
visitor.start(getDimension(), start, end);
for (int i = start; i <= end; i++) {
setEntry(i, visitor.visit(i, getEntry(i)));
}
return visitor.end();
}
/**
* Visits (and possibly alters) all entries of this vector in optimized order. The order in
* which the entries are visited is selected so as to lead to the most efficient implementation;
* it might depend on the concrete implementation of this abstract class.
*
* @param visitor the visitor to be used to process the entries of this vector
* @return the value returned by {@link RealVectorChangingVisitor#end()} at the end of the walk
* @since 3.1
*/
public double walkInOptimizedOrder(final RealVectorChangingVisitor visitor) {
return walkInDefaultOrder(visitor);
}
/**
* Visits (and possibly change) some entries of this vector in optimized order. The order in
* which the entries are visited is selected so as to lead to the most efficient implementation;
* it might depend on the concrete implementation of this abstract class.
*
* @param visitor visitor to be used to process the entries of this vector
* @param start the index of the first entry to be visited
* @param end the index of the last entry to be visited (inclusive)
* @return the value returned by {@link RealVectorChangingVisitor#end()} at the end of the walk
* @throws NumberIsTooSmallException if {@code end < start}.
* @throws OutOfRangeException if the indices are not valid.
* @since 3.1
*/
public double walkInOptimizedOrder(
final RealVectorChangingVisitor visitor, final int start, final int end)
throws NumberIsTooSmallException, OutOfRangeException {
return walkInDefaultOrder(visitor, start, end);
}
/** An entry in the vector. */
protected class Entry {
/** Index of this entry. */
private int index;
/** Simple constructor. */
public Entry() {
setIndex(0);
}
/**
* Get the value of the entry.
*
* @return the value of the entry.
*/
public double getValue() {
return getEntry(getIndex());
}
/**
* Set the value of the entry.
*
* @param value New value for the entry.
*/
public void setValue(double value) {
setEntry(getIndex(), value);
}
/**
* Get the index of the entry.
*
* @return the index of the entry.
*/
public int getIndex() {
return index;
}
/**
* Set the index of the entry.
*
* @param index New index for the entry.
*/
public void setIndex(int index) {
this.index = index;
}
}
/**
* Test for the equality of two real vectors. If all coordinates of two real vectors are exactly
* the same, and none are {@code NaN}, the two real vectors are considered to be equal. {@code
* NaN} coordinates are considered to affect globally the vector and be equals to each other -
* i.e, if either (or all) coordinates of the real vector are equal to {@code NaN}, the real
* vector is equal to a vector with all {@code NaN} coordinates.
*
* This method must be overriden by concrete subclasses of {@link RealVector} (the
* current implementation throws an exception).
*
* @param other Object to test for equality.
* @return {@code true} if two vector objects are equal, {@code false} if {@code other} is null,
* not an instance of {@code RealVector}, or not equal to this {@code RealVector} instance.
* @throws MathUnsupportedOperationException if this method is not overridden.
*/
@Override
public boolean equals(Object other) throws MathUnsupportedOperationException {
throw new MathUnsupportedOperationException();
}
/**
* {@inheritDoc}. This method must be overriden by concrete subclasses of {@link
* RealVector} (current implementation throws an exception).
*
* @throws MathUnsupportedOperationException if this method is not overridden.
*/
@Override
public int hashCode() throws MathUnsupportedOperationException {
throw new MathUnsupportedOperationException();
}
/**
* This class should rarely be used, but is here to provide a default implementation of
* sparseIterator(), which is implemented by walking over the entries, skipping those that are
* zero.
*
*
Concrete subclasses which are SparseVector implementations should make their own sparse
* iterator, rather than using this one.
*
*
This implementation might be useful for ArrayRealVector, when expensive operations which
* preserve the default value are to be done on the entries, and the fraction of non-default
* values is small (i.e. someone took a SparseVector, and passed it into the copy-constructor of
* ArrayRealVector)
*/
protected class SparseEntryIterator implements Iterator {
/** Dimension of the vector. */
private final int dim;
/** Last entry returned by {@link #next()}. */
private Entry current;
/** Next entry for {@link #next()} to return. */
private Entry next;
/** Simple constructor. */
protected SparseEntryIterator() {
dim = getDimension();
current = new Entry();
next = new Entry();
if (next.getValue() == 0) {
advance(next);
}
}
/**
* Advance an entry up to the next nonzero one.
*
* @param e entry to advance.
*/
protected void advance(Entry e) {
if (e == null) {
return;
}
do {
e.setIndex(e.getIndex() + 1);
} while (e.getIndex() < dim && e.getValue() == 0);
if (e.getIndex() >= dim) {
e.setIndex(-1);
}
}
/** {@inheritDoc} */
public boolean hasNext() {
return next.getIndex() >= 0;
}
/** {@inheritDoc} */
public Entry next() {
int index = next.getIndex();
if (index < 0) {
throw new NoSuchElementException();
}
current.setIndex(index);
advance(next);
return current;
}
/**
* {@inheritDoc}
*
* @throws MathUnsupportedOperationException in all circumstances.
*/
public void remove() throws MathUnsupportedOperationException {
throw new MathUnsupportedOperationException();
}
}
/**
* Returns an unmodifiable view of the specified vector. The returned vector has read-only
* access. An attempt to modify it will result in a {@link MathUnsupportedOperationException}.
* However, the returned vector is not immutable, since any modification of {@code v}
* will also change the returned view. For example, in the following piece of code
*
*
* RealVector v = new ArrayRealVector(2);
* RealVector w = RealVector.unmodifiableRealVector(v);
* v.setEntry(0, 1.2);
* v.setEntry(1, -3.4);
*
*
* the changes will be seen in the {@code w} view of {@code v}.
*
* @param v Vector for which an unmodifiable view is to be returned.
* @return an unmodifiable view of {@code v}.
*/
public static RealVector unmodifiableRealVector(final RealVector v) {
/**
* This anonymous class is an implementation of {@link RealVector} with read-only access. It
* wraps any {@link RealVector}, and exposes all methods which do not modify it. Invoking
* methods which should normally result in the modification of the calling {@link
* RealVector} results in a {@link MathUnsupportedOperationException}. It should be noted
* that {@link UnmodifiableVector} is not immutable.
*/
return new RealVector() {
/**
* {@inheritDoc}
*
* @throws MathUnsupportedOperationException in all circumstances.
*/
@Override
public RealVector mapToSelf(UnivariateFunction function)
throws MathUnsupportedOperationException {
throw new MathUnsupportedOperationException();
}
/** {@inheritDoc} */
@Override
public RealVector map(UnivariateFunction function) {
return v.map(function);
}
/** {@inheritDoc} */
@Override
public Iterator iterator() {
final Iterator i = v.iterator();
return new Iterator() {
/** The current entry. */
private final UnmodifiableEntry e = new UnmodifiableEntry();
/** {@inheritDoc} */
public boolean hasNext() {
return i.hasNext();
}
/** {@inheritDoc} */
public Entry next() {
e.setIndex(i.next().getIndex());
return e;
}
/**
* {@inheritDoc}
*
* @throws MathUnsupportedOperationException in all circumstances.
*/
public void remove() throws MathUnsupportedOperationException {
throw new MathUnsupportedOperationException();
}
};
}
/** {@inheritDoc} */
@Override
public Iterator sparseIterator() {
final Iterator i = v.sparseIterator();
return new Iterator() {
/** The current entry. */
private final UnmodifiableEntry e = new UnmodifiableEntry();
/** {@inheritDoc} */
public boolean hasNext() {
return i.hasNext();
}
/** {@inheritDoc} */
public Entry next() {
e.setIndex(i.next().getIndex());
return e;
}
/**
* {@inheritDoc}
*
* @throws MathUnsupportedOperationException in all circumstances.
*/
public void remove() throws MathUnsupportedOperationException {
throw new MathUnsupportedOperationException();
}
};
}
/** {@inheritDoc} */
@Override
public RealVector copy() {
return v.copy();
}
/** {@inheritDoc} */
@Override
public RealVector add(RealVector w) throws DimensionMismatchException {
return v.add(w);
}
/** {@inheritDoc} */
@Override
public RealVector subtract(RealVector w) throws DimensionMismatchException {
return v.subtract(w);
}
/** {@inheritDoc} */
@Override
public RealVector mapAdd(double d) {
return v.mapAdd(d);
}
/**
* {@inheritDoc}
*
* @throws MathUnsupportedOperationException in all circumstances.
*/
@Override
public RealVector mapAddToSelf(double d) throws MathUnsupportedOperationException {
throw new MathUnsupportedOperationException();
}
/** {@inheritDoc} */
@Override
public RealVector mapSubtract(double d) {
return v.mapSubtract(d);
}
/**
* {@inheritDoc}
*
* @throws MathUnsupportedOperationException in all circumstances.
*/
@Override
public RealVector mapSubtractToSelf(double d) throws MathUnsupportedOperationException {
throw new MathUnsupportedOperationException();
}
/** {@inheritDoc} */
@Override
public RealVector mapMultiply(double d) {
return v.mapMultiply(d);
}
/**
* {@inheritDoc}
*
* @throws MathUnsupportedOperationException in all circumstances.
*/
@Override
public RealVector mapMultiplyToSelf(double d) throws MathUnsupportedOperationException {
throw new MathUnsupportedOperationException();
}
/** {@inheritDoc} */
@Override
public RealVector mapDivide(double d) {
return v.mapDivide(d);
}
/**
* {@inheritDoc}
*
* @throws MathUnsupportedOperationException in all circumstances.
*/
@Override
public RealVector mapDivideToSelf(double d) throws MathUnsupportedOperationException {
throw new MathUnsupportedOperationException();
}
/** {@inheritDoc} */
@Override
public RealVector ebeMultiply(RealVector w) throws DimensionMismatchException {
return v.ebeMultiply(w);
}
/** {@inheritDoc} */
@Override
public RealVector ebeDivide(RealVector w) throws DimensionMismatchException {
return v.ebeDivide(w);
}
/** {@inheritDoc} */
@Override
public double dotProduct(RealVector w) throws DimensionMismatchException {
return v.dotProduct(w);
}
/** {@inheritDoc} */
@Override
public double cosine(RealVector w)
throws DimensionMismatchException, MathArithmeticException {
return v.cosine(w);
}
/** {@inheritDoc} */
@Override
public double getNorm() {
return v.getNorm();
}
/** {@inheritDoc} */
@Override
public double getL1Norm() {
return v.getL1Norm();
}
/** {@inheritDoc} */
@Override
public double getLInfNorm() {
return v.getLInfNorm();
}
/** {@inheritDoc} */
@Override
public double getDistance(RealVector w) throws DimensionMismatchException {
return v.getDistance(w);
}
/** {@inheritDoc} */
@Override
public double getL1Distance(RealVector w) throws DimensionMismatchException {
return v.getL1Distance(w);
}
/** {@inheritDoc} */
@Override
public double getLInfDistance(RealVector w) throws DimensionMismatchException {
return v.getLInfDistance(w);
}
/** {@inheritDoc} */
@Override
public RealVector unitVector() throws MathArithmeticException {
return v.unitVector();
}
/**
* {@inheritDoc}
*
* @throws MathUnsupportedOperationException in all circumstances.
*/
@Override
public void unitize() throws MathUnsupportedOperationException {
throw new MathUnsupportedOperationException();
}
/** {@inheritDoc} */
@Override
public RealMatrix outerProduct(RealVector w) {
return v.outerProduct(w);
}
/** {@inheritDoc} */
@Override
public double getEntry(int index) throws OutOfRangeException {
return v.getEntry(index);
}
/**
* {@inheritDoc}
*
* @throws MathUnsupportedOperationException in all circumstances.
*/
@Override
public void setEntry(int index, double value) throws MathUnsupportedOperationException {
throw new MathUnsupportedOperationException();
}
/**
* {@inheritDoc}
*
* @throws MathUnsupportedOperationException in all circumstances.
*/
@Override
public void addToEntry(int index, double value)
throws MathUnsupportedOperationException {
throw new MathUnsupportedOperationException();
}
/** {@inheritDoc} */
@Override
public int getDimension() {
return v.getDimension();
}
/** {@inheritDoc} */
@Override
public RealVector append(RealVector w) {
return v.append(w);
}
/** {@inheritDoc} */
@Override
public RealVector append(double d) {
return v.append(d);
}
/** {@inheritDoc} */
@Override
public RealVector getSubVector(int index, int n)
throws OutOfRangeException, NotPositiveException {
return v.getSubVector(index, n);
}
/**
* {@inheritDoc}
*
* @throws MathUnsupportedOperationException in all circumstances.
*/
@Override
public void setSubVector(int index, RealVector w)
throws MathUnsupportedOperationException {
throw new MathUnsupportedOperationException();
}
/**
* {@inheritDoc}
*
* @throws MathUnsupportedOperationException in all circumstances.
*/
@Override
public void set(double value) throws MathUnsupportedOperationException {
throw new MathUnsupportedOperationException();
}
/** {@inheritDoc} */
@Override
public double[] toArray() {
return v.toArray();
}
/** {@inheritDoc} */
@Override
public boolean isNaN() {
return v.isNaN();
}
/** {@inheritDoc} */
@Override
public boolean isInfinite() {
return v.isInfinite();
}
/** {@inheritDoc} */
@Override
public RealVector combine(double a, double b, RealVector y)
throws DimensionMismatchException {
return v.combine(a, b, y);
}
/**
* {@inheritDoc}
*
* @throws MathUnsupportedOperationException in all circumstances.
*/
@Override
public RealVector combineToSelf(double a, double b, RealVector y)
throws MathUnsupportedOperationException {
throw new MathUnsupportedOperationException();
}
/** An entry in the vector. */
class UnmodifiableEntry extends Entry {
/** {@inheritDoc} */
@Override
public double getValue() {
return v.getEntry(getIndex());
}
/**
* {@inheritDoc}
*
* @throws MathUnsupportedOperationException in all circumstances.
*/
@Override
public void setValue(double value) throws MathUnsupportedOperationException {
throw new MathUnsupportedOperationException();
}
}
};
}
}