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 *      http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.commons.math3.util;


Provides a standard interface for double arrays. Allows different array implementations to support various storage mechanisms such as automatic expansion, contraction, and array "rolling".
/** * Provides a standard interface for double arrays. Allows different * array implementations to support various storage mechanisms * such as automatic expansion, contraction, and array "rolling". * */
public interface DoubleArray {
Returns the number of elements currently in the array. Please note that this may be different from the length of the internal storage array.
Returns:number of elements
/** * Returns the number of elements currently in the array. Please note * that this may be different from the length of the internal storage array. * * @return number of elements */
int getNumElements();
Returns the element at the specified index. Note that if an out of bounds index is supplied a ArrayIndexOutOfBoundsException will be thrown.
Params:
  • index – index to fetch a value from
Throws:
Returns:value stored at the specified index
/** * Returns the element at the specified index. Note that if an * out of bounds index is supplied a ArrayIndexOutOfBoundsException * will be thrown. * * @param index index to fetch a value from * @return value stored at the specified index * @throws ArrayIndexOutOfBoundsException if <code>index</code> is less than * zero or is greater than <code>getNumElements() - 1</code>. */
double getElement(int index);
Sets the element at the specified index. If the specified index is greater than getNumElements() - 1, the numElements property is increased to index +1 and additional storage is allocated (if necessary) for the new element and all (uninitialized) elements between the new element and the previous end of the array).
Params:
  • index – index to store a value in
  • value – value to store at the specified index
Throws:
/** * Sets the element at the specified index. If the specified index is greater than * <code>getNumElements() - 1</code>, the <code>numElements</code> property * is increased to <code>index +1</code> and additional storage is allocated * (if necessary) for the new element and all (uninitialized) elements * between the new element and the previous end of the array). * * @param index index to store a value in * @param value value to store at the specified index * @throws ArrayIndexOutOfBoundsException if <code>index</code> is less than * zero. */
void setElement(int index, double value);
Adds an element to the end of this expandable array
Params:
  • value – to be added to end of array
/** * Adds an element to the end of this expandable array * * @param value to be added to end of array */
void addElement(double value);
Adds elements to the end of this expandable array
Params:
  • values – to be added to end of array
/** * Adds elements to the end of this expandable array * * @param values to be added to end of array */
void addElements(double[] values);

Adds an element to the end of the array and removes the first element in the array. Returns the discarded first element. The effect is similar to a push operation in a FIFO queue.

Example: If the array contains the elements 1, 2, 3, 4 (in that order) and addElementRolling(5) is invoked, the result is an array containing the entries 2, 3, 4, 5 and the value returned is 1.

Params:
  • value – the value to be added to the array
Returns:the value which has been discarded or "pushed" out of the array by this rolling insert
/** * <p> * Adds an element to the end of the array and removes the first * element in the array. Returns the discarded first element. * The effect is similar to a push operation in a FIFO queue. * </p> * <p> * Example: If the array contains the elements 1, 2, 3, 4 (in that order) * and addElementRolling(5) is invoked, the result is an array containing * the entries 2, 3, 4, 5 and the value returned is 1. * </p> * * @param value the value to be added to the array * @return the value which has been discarded or "pushed" out of the array * by this rolling insert */
double addElementRolling(double value);
Returns a double[] array containing the elements of this DoubleArray. If the underlying implementation is array-based, this method should always return a copy, rather than a reference to the underlying array so that changes made to the returned array have no effect on the DoubleArray.
Returns:all elements added to the array
/** * Returns a double[] array containing the elements of this * <code>DoubleArray</code>. If the underlying implementation is * array-based, this method should always return a copy, rather than a * reference to the underlying array so that changes made to the returned * array have no effect on the <code>DoubleArray.</code> * * @return all elements added to the array */
double[] getElements();
Clear the double array
/** * Clear the double array */
void clear(); }