SparseBinSearchDoubleArray (OpenIMAJ master project 1.3.10 API)

java.lang.Object
- org.openimaj.util.array.SparseDoubleArray
- - org.openimaj.util.array.SparseBinSearchDoubleArray

All Implemented Interfaces:

Readable, ReadableASCII, ReadableBinary, ReadWriteable, Writeable, WriteableASCII, WriteableBinary, Concatenatable<SparseDoubleArray,SparseDoubleArray>
```
public class SparseBinSearchDoubleArray
extends SparseDoubleArray
```
A Sparse array of double values implemented using a pair of sorted parallel arrays. The first array holds the indexes of the non-zero elements in ascending order; the second holds the corresponding values.
Element access has worst-case O(log n) performance. Appends (where the index being added is greater than the existing indices) has O(1) complexity. Random puts have worst case O(n + log n) complexity. Complexity for getting values by increasing index for iteration through the non-zero values is O(1).
In summary, this implementation has good access performance, and is fast for appending values, but slow for putting at random indices. It is is optimal for a scenario where you first create the sparse array and put values in order of increasing indices, and later use the array mostly for reading.

Author:

Jonathon Hare (jsh2@ecs.soton.ac.uk)

See Also:

"http://stackoverflow.com/questions/1880804/java-time-efficient-sparse-1d-array-double"

Nested Class Summary
- Nested classes/interfaces inherited from class org.openimaj.util.array.SparseDoubleArray
  SparseDoubleArray.DualEntry, SparseDoubleArray.Entry

Field Summary

Fields
Modifier and Type Field and Description

protected int[] keys

protected int used

protected double[] values
- Fields inherited from class org.openimaj.util.array.SparseDoubleArray
  DEFAULT_CAPACITY, length

Fields
Modifier and Type	Field and Description
`protected int[]`	`keys`
`protected int`	`used`
`protected double[]`	`values`

Constructor Summary

Constructors
Constructor and Description
`SparseBinSearchDoubleArray(double[] values)` Construct from an existing array of values
`SparseBinSearchDoubleArray(int length)` Construct the array with the given length
`SparseBinSearchDoubleArray(int length, float density)` Construct the array with the given length and expected density
`SparseBinSearchDoubleArray(int length, int capacity)` Construct the array with the given length and capacity for non-zero elements
`SparseBinSearchDoubleArray(int length, int used, int[] keys, double[] values)` Generate a new `SparseBinSearchDoubleArray` wrapper which works around an existing array of keys and values

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`compact()` Compact the space being used by the array if possible.
`SparseDoubleArray`	`copy()` Deep copy the array.
`Iterable<SparseDoubleArray.Entry>`	`entries()` Provide an iterator over the non-zero values.
`boolean`	`equals(Object obj)`
`double`	`get(int key)` Get the value at the given index.
`int`	`hashCode()`
`double`	`increment(int key, double value)` Increment the value at the given index.
`int[]`	`indices()`
`boolean`	`isUsed(int key)` Check whether the given index is used (i.e.
`SparseDoubleArray`	`reverse()` Reverse the elements, returning this.
`double`	`set(int key, double value)` Set the value at the given index.
`Iterable<SparseDoubleArray.DualEntry>`	`unionEntries(SparseBinSearchDoubleArray otherArray)` Provide an iterator over the union of values present in both this array and another array.
`Iterable<SparseDoubleArray.DualEntry>`	`unionEntries(SparseDoubleArray otherArray)` Provide an iterator over the union of values present in both this array and another array.
`int`	`used()`
`double[]`	`values()`

Methods inherited from class org.openimaj.util.array.SparseDoubleArray
add, addInplace, asciiHeader, binaryHeader, concatenate, concatenate, concatenateArrays, density, dotProduct, intersectEntries, length, maxIndex, maxValue, minIndex, minValue, multiply, multiplyInplace, readASCII, readBinary, setLength, size, subtract, subtractInplace, sumValues, sumValuesSquared, toArray, toArray, writeASCII, writeBinary

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - keys
```
protected int[] keys
```
  - values
```
protected double[] values
```
  - used
```
protected int used
```
- Constructor Detail
  - SparseBinSearchDoubleArray
```
public SparseBinSearchDoubleArray(double[] values)
```
    Construct from an existing array of values
    
    Parameters:
    
    values - the values
  - SparseBinSearchDoubleArray
```
public SparseBinSearchDoubleArray(int length,
                                  int used,
                                  int[] keys,
                                  double[] values)
```
    Generate a new SparseBinSearchDoubleArray wrapper which works around an existing array of keys and values
    
    Parameters:
    
    length -
    
    used -
    
    keys -
    
    values -
  - SparseBinSearchDoubleArray
```
public SparseBinSearchDoubleArray(int length)
```
    Construct the array with the given length
    
    Parameters:
    
    length - the length
  - SparseBinSearchDoubleArray
```
public SparseBinSearchDoubleArray(int length,
                                  int capacity)
```
    Construct the array with the given length and capacity for non-zero elements
    
    Parameters:
    
    length - the length
    
    capacity - the capacity
  - SparseBinSearchDoubleArray
```
public SparseBinSearchDoubleArray(int length,
                                  float density)
```
    Construct the array with the given length and expected density
    
    Parameters:
    
    length - the length
    
    density - the density
- Method Detail
  - indices
```
public int[] indices()
```
    Specified by:
    
    indices in class SparseDoubleArray
    
    Returns:
    
    the indices of the non-zero valued entries of the array.
  - values
```
public double[] values()
```
    Specified by:
    
    values in class SparseDoubleArray
    
    Returns:
    
    the packed non-zero valued entries of the array.
  - unionEntries
```
public Iterable<SparseDoubleArray.DualEntry> unionEntries(SparseDoubleArray otherArray)
```
    Description copied from class: SparseDoubleArray
    
    Provide an iterator over the union of values present in both this array and another array. Values where both arrays are zero are skipped.
    Note: the SparseDoubleArray.DualEntry returned by the iterator is always the same object. In addition, the iterator cannot affect the value of anything in the array (i.e. changing anything in the SparseDoubleArray.DualEntry has no effect on the actual array).
    
    Overrides:
    
    unionEntries in class SparseDoubleArray
    
    Parameters:
    
    otherArray - the second array
    
    Returns:
    
    an iterator over the non-zero values.
  - unionEntries
```
public Iterable<SparseDoubleArray.DualEntry> unionEntries(SparseBinSearchDoubleArray otherArray)
```
    Provide an iterator over the union of values present in both this array and another array. Values where both arrays are zero are skipped.
    Note: the SparseDoubleArray.DualEntry returned by the iterator is always the same object. In addition, the iterator cannot affect the value of anything in the array (i.e. changing anything in the SparseDoubleArray.DualEntry has no effect on the actual array).
    
    Parameters:
    
    otherArray - the second array
    
    Returns:
    
    an iterator over the non-zero values.
  - entries
```
public Iterable<SparseDoubleArray.Entry> entries()
```
    Description copied from class: SparseDoubleArray
    
    Provide an iterator over the non-zero values.
    Note: the SparseDoubleArray.Entry returned by the iterator is always the same object. In addition, the iterator cannot affect the value of anything in the array (i.e. changing anything in the SparseDoubleArray.Entry has no effect on the actual array).
    
    Specified by:
    
    entries in class SparseDoubleArray
    
    Returns:
    
    an iterator over the non-zero values.
  - equals
```
public boolean equals(Object obj)
```
    Overrides:
    
    equals in class Object
  - get
```
public double get(int key)
```
    Description copied from class: SparseDoubleArray
    
    Get the value at the given index.
    
    Specified by:
    
    get in class SparseDoubleArray
    
    Parameters:
    
    key - the index
    
    Returns:
    
    the value at the index.
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class Object
  - isUsed
```
public boolean isUsed(int key)
```
    Description copied from class: SparseDoubleArray
    
    Check whether the given index is used (i.e. has a non-zero value)
    
    Specified by:
    
    isUsed in class SparseDoubleArray
    
    Parameters:
    
    key - the index
    
    Returns:
    
    true if not used; false otherwise.
  - set
```
public double set(int key,
                  double value)
```
    Description copied from class: SparseDoubleArray
    
    Set the value at the given index.
    
    Specified by:
    
    set in class SparseDoubleArray
    
    Parameters:
    
    key - the index.
    
    value - the value to set.
    
    Returns:
    
    the value
  - increment
```
public double increment(int key,
                        double value)
```
    Description copied from class: SparseDoubleArray
    
    Increment the value at the given index.
    
    Specified by:
    
    increment in class SparseDoubleArray
    
    Parameters:
    
    key - the index
    
    value - the amount to increment by.
    
    Returns:
    
    the new value
  - used
```
public int used()
```
    Specified by:
    
    used in class SparseDoubleArray
    
    Returns:
    
    the number of non-zero entries in the array
  - compact
```
public void compact()
```
    Description copied from class: SparseDoubleArray
    
    Compact the space being used by the array if possible.
    
    Specified by:
    
    compact in class SparseDoubleArray
  - copy
```
public SparseDoubleArray copy()
```
    Description copied from class: SparseDoubleArray
    
    Deep copy the array.
    
    Specified by:
    
    copy in class SparseDoubleArray
    
    Returns:
    
    a deep copy of the array
  - reverse
```
public SparseDoubleArray reverse()
```
    Description copied from class: SparseDoubleArray
    
    Reverse the elements, returning this.
    
    Specified by:
    
    reverse in class SparseDoubleArray
    
    Returns:
    
    this array

Class SparseBinSearchDoubleArray

Nested Class Summary

Nested classes/interfaces inherited from class org.openimaj.util.array.SparseDoubleArray

Field Summary

Fields inherited from class org.openimaj.util.array.SparseDoubleArray

Constructor Summary

Method Summary

Methods inherited from class org.openimaj.util.array.SparseDoubleArray

Methods inherited from class java.lang.Object

Field Detail

keys

values

used

Constructor Detail

SparseBinSearchDoubleArray

SparseBinSearchDoubleArray

SparseBinSearchDoubleArray

SparseBinSearchDoubleArray

SparseBinSearchDoubleArray

Method Detail

indices

values

unionEntries

unionEntries

entries

equals

get

hashCode

isUsed

set

increment

used

compact

copy

reverse