ScenarioArray (OpenGamma Strata Data)

Type Parameters:

T - the type of each individual value

All Known Implementing Classes:

CurrencyScenarioArray, DoubleScenarioArray, FxRateScenarioArray, MultiCurrencyScenarioArray
```
public interface ScenarioArray<T>
```
An array of values, one for each scenario.
Implementations of this interface provide scenario-specific values.
In the simplest case, this might be a list of values, one for each scenario. This is handled by this factory methods on this interface.
There are two obvious reasons for creating implementations of this interface with special handling for certain types of value:
- Reducing memory usage
- Improving performance
For example, if the system stores multiple copies of a curve as a list it must store the x-values with each copy of the curve. This data is mostly redundant as the x-values are the same in every scenario. A custom data type for storing scenario data for a curve can store one set of x-values shared between all scenarios, reducing memory footprint.
When dealing with primitive data it is likely be more efficient to store the scenario values in a primitive array instead of using a list. This removes the need for boxing and reduces memory footprint. Also, if a function calculates values for all scenarios at the same time, it is likely to be more efficient if the data is stored in arrays as the values will be stored in a contiguous block of memory.
The generic type parameter is the type of the single value associated with each scenario. For example, in the case of optimized curve storage, the single value is a curve.

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method and Description
`T`	`get(int scenarioIndex)` Gets the value at the specified scenario index.
`int`	`getScenarioCount()` Gets the number of scenarios.
`static <T> ScenarioArray<T>`	`of(int scenarioCount, IntFunction<T> valueFunction)` Obtains an instance using a function to create the entries.
`static <T> ScenarioArray<T>`	`of(List<T> values)` Obtains an instance from the specified list of values.
`static <T> ScenarioArray<T>`	`of(T... values)` Obtains an instance from the specified array of values.
`static <T> ScenarioArray<T>`	`ofSingleValue(int scenarioCount, T value)` Obtains an instance from a single value where the value applies to all scenarios.
`default Stream<T>`	`stream()` Returns a stream of the values.

- Method Detail
  - of
```
@SafeVarargs
static <T> ScenarioArray<T> of(T... values)
```
    Obtains an instance from the specified array of values.
    
    Type Parameters:
    
    T - the type of the value
    
    Parameters:
    
    values - the values, one value for each scenario
    
    Returns:
    
    an instance with the specified values
  - of
```
static <T> ScenarioArray<T> of(List<T> values)
```
    Obtains an instance from the specified list of values.
    
    Type Parameters:
    
    T - the type of the value
    
    Parameters:
    
    values - the values, one value for each scenario
    
    Returns:
    
    an instance with the specified values
  - of
```
static <T> ScenarioArray<T> of(int scenarioCount,
                               IntFunction<T> valueFunction)
```
    Obtains an instance using a function to create the entries.
    The function is passed the scenario index and returns the value for that index.
    
    Type Parameters:
    
    T - the type of the value
    
    Parameters:
    
    scenarioCount - the number of scenarios
    
    valueFunction - the function used to obtain each value
    
    Returns:
    
    an instance initialized using the function
    
    Throws:
    
    IllegalArgumentException - is size is zero or less
  - ofSingleValue
```
static <T> ScenarioArray<T> ofSingleValue(int scenarioCount,
                                          T value)
```
    Obtains an instance from a single value where the value applies to all scenarios.
    
    Type Parameters:
    
    T - the type of the value
    
    Parameters:
    
    scenarioCount - the nnumber of scenarios
    
    value - the single value, used for all scenarios
    
    Returns:
    
    an instance with the specified values
  - getScenarioCount
```
int getScenarioCount()
```
    Gets the number of scenarios.
    
    Returns:
    
    the number of scenarios
  - get
```
T get(int scenarioIndex)
```
    Gets the value at the specified scenario index.
    
    Parameters:
    
    scenarioIndex - the zero-based index of the scenario
    
    Returns:
    
    the value at the specified index
    
    Throws:
    
    IndexOutOfBoundsException - if the index is invalid
  - stream
```
default Stream<T> stream()
```
    Returns a stream of the values.
    The stream will return the value for each scenario.
    
    Returns:
    
    a stream of the values

Copyright 2009-Present by OpenGamma Inc. and individual contributors
Apache v2 licensed
Additional documentation can be found at strata.opengamma.io.

Interface ScenarioArray<T>

Method Summary

Method Detail

of

of

of

ofSingleValue

getScenarioCount

get

stream