Package org.anchoranalysis.math.optimization

Class SearchClosestValueMonoticallyIncreasing

Object

org.anchoranalysis.math.optimization.SearchClosestValueMonoticallyIncreasing

public class SearchClosestValueMonoticallyIncreasing
extends Object

Given a monotonically increasing function of an integer, determine the input value that provides an output value as close to target as possible.

The input-values must be integers, and have a minimum bound.

It begins at the minimum-bound, and in a similar manner to exponential search, successively doubles, until a lower and upper bound are found.

It then proceeds with a binary-search-style recursive evaluation to find the integer value that produces the exact closest value to target.

An upper bound on the input-values may also be optionally imposed via boundUpper.

Author:

Owen Feehan

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	SearchClosestValueMonoticallyIncreasing.ValueFunction	The function that calculates the output value for a particular input int.

Constructor Summary

Constructors

Constructor	Description
SearchClosestValueMonoticallyIncreasing(double target, SearchClosestValueMonoticallyIncreasing.ValueFunction function)	Create without an upper bound.
SearchClosestValueMonoticallyIncreasing(double target, SearchClosestValueMonoticallyIncreasing.ValueFunction function, IntPredicate boundUpper)

Method Summary

Modifier and Type	Method	Description
int	findOptimalInput(int boundLower)	Finds the input value that produces a calculated-value that is closest to target.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

SearchClosestValueMonoticallyIncreasing

public SearchClosestValueMonoticallyIncreasing(double target, SearchClosestValueMonoticallyIncreasing.ValueFunction function)

Create without an upper bound.

Parameters:

target - the target value to try and be closest to when evaluating function on differing inputs.

function - calculates an output value for a particular input integer.

SearchClosestValueMonoticallyIncreasing

public SearchClosestValueMonoticallyIncreasing(double target, SearchClosestValueMonoticallyIncreasing.ValueFunction function, IntPredicate boundUpper)

Method Details

findOptimalInput

public int findOptimalInput(int boundLower)

Finds the input value that produces a calculated-value that is closest to target.

Parameters:

boundLower - a lower bound on the input range, inclusive.

Returns:

the input-value that is optimal to produce the closest value to target when evaluated using calculateValue.