WeightingFunction (OpenGamma Strata)

All Superinterfaces:

Named
```
public interface WeightingFunction
extends Named
```
A function to allow a smooth weighing between two functions.
If two functions f(x) and g(x) fit the data set (x_i,y_i) at the points x_a and x_b (i.e. f(x_a) = g(x_a) = y_a and f(x_b) = g(x_b) = y_b), then a weighted function h(x) = w(x)f(x) + (1-w(x))*g(x) with 0 <= w(x) <= 1 will also fit the points a and b

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method	Description
`double`	`getWeight(double y)`	Gets the weight.
`default double`	`getWeight(double[] xs, int index, double x)`	Gets the function weight for point x, based on the lower bound index.
`static WeightingFunction`	`of(String uniqueName)`	Obtains an instance from the specified unique name.

Methods inherited from interface com.opengamma.strata.collect.named.Named
getName

- Method Detail
  - of
```
static WeightingFunction of(String uniqueName)
```
    Obtains an instance from the specified unique name.
    
    Parameters:
    
    uniqueName - the unique name
    
    Returns:
    
    the index
    
    Throws:
    
    IllegalArgumentException - if the name is not known
  - getWeight
```
default double getWeight(double[] xs,
                         int index,
                         double x)
```
    Gets the function weight for point x, based on the lower bound index.
    
    Parameters:
    
    xs - the independent data points
    
    index - the index of the data point below x
    
    x - the x-point to find the weight for
    
    Returns:
    
    the weight
  - getWeight
```
double getWeight(double y)
```
    Gets the weight.
    The condition that must be satisfied by all weight functions is that w(1) = 1, w(0) = 0 and dw(y)/dy <= 0 - i.e. w(y) is monotonically decreasing.
    
    Parameters:
    
    y - a value between 0 and 1
    
    Returns:
    
    the weight