public abstract class Interpolator extends Object implements IEvaluator
| Modifier | Constructor and Description |
|---|---|
protected |
Interpolator(EvaluatorGroup group)
Initializes a new instance.
|
protected |
Interpolator(Interpolator existingInstance,
CopyContext context)
Initializes a new instance as a copy of an existing instance.
|
| Modifier and Type | Method and Description |
|---|---|
abstract Object |
clone(CopyContext context)
Clones this object using the specified context.
|
void |
dispose()
Releases any resources associated with this instance.
|
protected abstract void |
dispose(boolean disposing)
Releases any resources associated with this instance.
|
abstract TimeIntervalCollection |
getAvailabilityIntervals(TimeIntervalCollection consideredIntervals)
Gets the intervals over which data is available.
|
IEvaluator |
getCachingWrapper()
Gets a version of this evaluator that caches the previously computed value so that if it is evaluated
twice at the same date the computation is done only once.
|
EvaluatorGroup |
getGroup()
Gets the group that contains this evaluator.
|
abstract boolean |
getIsThreadSafe()
Gets a value indicating whether the methods on this instance are safe to call from
multiple threads simultaneously.
|
abstract int |
getRequiredDataPoints(int degree,
int inputOrder)
Calculates the number of data points needed to interpolate with the desired degree of accuracy.
|
double[] |
interpolate(double x,
double[] xTable,
double[] yTable,
int yStride,
int inputOrder,
int outputOrder)
Interpolates values using this interpolation algorithm.
|
abstract double[] |
interpolate(double x,
double[] xTable,
double[] yTable,
int yStride,
int inputOrder,
int outputOrder,
int startIndex,
int length)
Interpolates values using this interpolation algorithm.
|
double[] |
interpolateWithDegree(double x,
double[] xTable,
double[] yTable,
int degree,
int yStride,
int inputOrder,
int outputOrder)
Interpolates values using this interpolation algorithm.
|
abstract boolean |
isAvailable(JulianDate date)
Determines if valid data is available for the given
JulianDate. |
abstract void |
updateEvaluatorReferences(CopyContext context)
Updates the evaluator references held by this object using the reference-to-reference
mapping in the specified
CopyContext. |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, waitcloseprotected Interpolator(@Nonnull EvaluatorGroup group)
group - The group that contains this evaluator.ArgumentNullException - Thrown when group is null.protected Interpolator(@Nonnull Interpolator existingInstance, @Nonnull CopyContext context)
See ICloneWithContext.clone(CopyContext) for more information about how to implement this constructor
in a derived class.
existingInstance - The existing instance to copy.context - A CopyContext that controls the depth of the copy.ArgumentNullException - Thrown when existingInstance or context is null.public abstract void updateEvaluatorReferences(CopyContext context)
CopyContext.
The following example shows how to implement this method for an evaluator that contains a nested evaluator:
@Override
public final void updateEvaluatorReferences(CopyContext context) {
m_nestedEvaluator = context.updateReference(m_nestedEvaluator);
}
This method is called by EvaluatorGroup and usually does not need to be
called directly by users. EvaluatorGroup uses this method to replace references
to shared evaluators with references to caching versions of the evaluators.
To implement this method, call CopyContext.updateReference(T) on each evaluator reference
held by your evaluator and assign the return value back to the field.
updateEvaluatorReferences in interface IEvaluatorcontext - The context that specifies the reference mapping.public abstract Object clone(CopyContext context)
This method should be implemented to call a copy constructor on the class of the
object being cloned. The copy constructor should take the CopyContext as a parameter
in addition to the existing instance to copy. The copy constructor should first call
CopyContext.addObjectMapping(T, T) to identify the newly constructed instance
as a copy of the existing instance. It should then copy all fields, using
CopyContext.updateReference(T) to copy any reference fields.
A typical implementation of ICloneWithContext:
public static class MyClass implements ICloneWithContext {
public MyClass(MyClass existingInstance, CopyContext context) {
context.addObjectMapping(existingInstance, this);
someReference = context.updateReference(existingInstance.someReference);
}
@Override
public final Object clone(CopyContext context) {
return new MyClass(this, context);
}
private Object someReference;
}
In general, all fields that are reference types should be copied with a call to
CopyContext.updateReference(T). There are a couple of exceptions:
If one of these exceptions applies, the CopyContext should be given an opportunity
to update the reference before the reference is copied explicitly. Use
CopyContext.updateReference(T) to update the reference. If CopyContext.updateReference(T) returns
the original object, indicating that the context does not have a replacement registered,
then copy the object manually by invoking a Clone method, a copy constructor, or by manually
constructing a new instance and copying the values.
alwaysCopy = context.updateReference(existingInstance.alwaysCopy);
if (existingInstance.alwaysCopy != null && alwaysCopy == existingInstance.alwaysCopy) {
alwaysCopy = (AlwaysCopy) existingInstance.alwaysCopy.clone(context);
}
If you are implementing an evaluator (a class that implements IEvaluator), the
IEvaluator.updateEvaluatorReferences(agi.foundation.infrastructure.CopyContext) method shares some responsibilities with the
copy context constructor. Code duplication can be avoided by doing the following:
CopyContext.updateReference(T). You should still call CopyContext.updateReference(T) on any references to
non-evaluators.
IEvaluator.updateEvaluatorReferences(agi.foundation.infrastructure.CopyContext) as the last line in the constructor and pass it the
same CopyContext passed to the constructor.
IEvaluator.updateEvaluatorReferences(agi.foundation.infrastructure.CopyContext) as normal. See the reference documentation for
IEvaluator.updateEvaluatorReferences(agi.foundation.infrastructure.CopyContext) for more information on implementing that method.
public MyClass(MyClass existingInstance, CopyContext context) {
super(existingInstance, context);
someReference = context.updateReference(existingInstance.someReference);
evaluatorReference = existingInstance.evaluatorReference;
updateEvaluatorReferences(context);
}
@Override
public void updateEvaluatorReferences(CopyContext context) {
evaluatorReference = context.updateReference(evaluatorReference);
}
@Override
public Object clone(CopyContext context) {
return new MyClass(this, context);
}
private Object someReference;
private IEvaluator evaluatorReference;clone in interface ICloneWithContextcontext - The context to use to perform the copy.public final void dispose()
dispose in interface IDisposableprotected abstract void dispose(boolean disposing)
disposing - true to release both managed and unmanaged resources;
false to release only unmanaged resources.public abstract TimeIntervalCollection getAvailabilityIntervals(TimeIntervalCollection consideredIntervals)
getAvailabilityIntervals in interface IAvailabilityconsideredIntervals - The intervals over which availability information is needed. Note that the returned availability
intervals may indicate availability outside of these intervals of consideration.public abstract boolean isAvailable(@Nonnull JulianDate date)
JulianDate.isAvailable in interface IAvailabilitydate - The date for which to check availability.true if valid data is available for this date; otherwise false.public abstract boolean getIsThreadSafe()
If this property is true, all methods and properties are guaranteed to be thread safe.
Conceptually, an object that returns true for this method acts as if there is a lock
protecting each method and property such that only one thread at a time can be inside any method or
property in the class. In reality, such locks are generally not used and are in fact discouraged. However,
the user must not experience any exceptions or inconsistent behavior that would not be experienced if such
locks were used.
If this property is false, the behavior when using this class from multiple threads
simultaneously is undefined and may include inconsistent results and exceptions. Clients wishing to use
multiple threads should call CopyForAnotherThread.copy(T) to get a separate instance of the
object for each thread.
getIsThreadSafe in interface IThreadAwarepublic final EvaluatorGroup getGroup()
getGroup in interface IEvaluatorpublic final IEvaluator getCachingWrapper()
This method is called by EvaluatorGroup to create a caching version of an evaluator
that is shared between multiple computations.
To implement this method in your own evaluator, construct and return a caching version of the evaluator's base class.
For example, if your evaluator implements IEvaluator1 directly, return an instance of
CachingEvaluator. In many cases, such as when implementing a PointEvaluator
this method does not need to be overridden because the default implementation returns an appropriate
caching wrapper already. If you do not want the last value computed by your evaluator to ever be cached, or
if your evaluator does its own caching internally, this method can return this.
Shows an example implementation in an evaluator that implements IEvaluator1
directly, where T is double.
@Override
public IEvaluator getCachingWrapper() {
return new CachingEvaluator<Double>(this);
}getCachingWrapper in interface IEvaluatorthis should be returned by this method.public abstract int getRequiredDataPoints(int degree,
int inputOrder)
degree - The degree of polynomial approximation desired.inputOrder - The order of the input data.@Nonnull public final double[] interpolate(double x, @Nonnull double[] xTable, @Nonnull double[] yTable, int yStride, int inputOrder, int outputOrder)
The xTable array should contain one more than the desired interpolation degree.
For example, for a 7th degree interpolation, xTable should contain 8 elements.
The yTable array should contain a number of elements equal to:
* * ( + 1)
x - The independent variable for which the dependent variables will be interpolated.xTable - The array of independent variables to use to interpolate. The values
in this array must be in increasing order and the same value must not occur twice in the array.yTable - The array of dependent variables to use to interpolate. For a set of three
dependent values (p,q,w) and their derivatives (dp, dq, dw) at time 1 and time 2 this should be
as follows: {p1, q1, w1, dp1, dq1, dw1, p2, q2, w2, dp2, dq2, dw2}.yStride - The number of dependent variable values in yTable corresponding to
each independent variable value in xTable. If inputOrder
is greater than 0, this is also the number of first derivative values, second derivative
values, etc. corresponding to each value in xTable.inputOrder - The number of dependent variable derivatives in yTable. If this value is 0,
the yTable is assumed to contain only dependent variable values, with each
yStride of them corresponding to a single independent variable in the
xTable. If this value is 1, the yTable is assumed to
contain not only the dependent variable values but also their derivatives. There are
yStride dependent variable values followed by yStride
dependent variable first derivatives corresponding to each independent variable value
in xTable. Similarly, if this value is 2, the
yTable contains dependent variable values, first derivatives, and second derivatives.outputOrder - The number of derivatives to return. To return just the dependent variable values,
pass 0 for this parameter. To return the first derivatives along with the dependent variable values, pass 1.
To retrieve the second derivatives as well, pass 2. Note that not all interpolation algorithms are capable
of returning second derivative information, and if a higher outputOrder
is requested than the algorithm is able to provide, the highest order derivative
will be returned and the request for the higher order derivatives is ignored.yStride elements,
each of which is an interpolated dependent variable value. If outputOrder
is 1 or greater, the array contains an additional yStride elements,
each of which is an interpolated dependent variable first derivative. Lastly, if
outputOrder is 2 or greater, the array contains another additional
yStride elements, each of which is an interpolated variable second
derivative. Note that if the interpolation algorithm is not capable of returning the degree of derivative
requested, it will simply return the highest order derivative available.ArgumentNullException - Thrown when xTable or yTable is null.@Nonnull public abstract double[] interpolate(double x, @Nonnull double[] xTable, @Nonnull double[] yTable, int yStride, int inputOrder, int outputOrder, int startIndex, int length)
The xTable array should contain one more than the desired interpolation degree.
For example, for a 7th degree interpolation, xTable should contain 8 elements.
The yTable array should contain a number of elements equal to:
* * ( + 1)
x - The independent variable for which the dependent variables will be interpolated.xTable - The array of independent variables to use to interpolate. The values
in this array must be in increasing order and the same value must not occur twice in the array.yTable - The array of dependent variables to use to interpolate.
There can be multiple values corresponding to each independent values in xTable.
For a set of three dependent values (p,q,w) and their derivatives (dp, dq, dw) at time 1 and time 2
this should be as follows: {p1, q1, w1, dp1, dq1, dw1, p2, q2, w2, dp2, dq2, dw2}.yStride - The number of dependent variable values in yTable corresponding to
each independent variable value in xTable. If inputOrder
is greater than 0, this is also the number of first derivative values, second derivative
values, etc. corresponding to each value in xTable.inputOrder - The number of dependent variable derivatives in yTable. If this value is 0,
the yTable is assumed to contain only dependent variable values, with each
yStride of them corresponding to a single independent variable in the
xTable. If this value is 1, the yTable is assumed to
contain not only the dependent variable values but also their derivatives. There are
yStride dependent variable values followed by yStride
dependent variable first derivatives corresponding to each independent variable value
in xTable. Similarly, if this value is 2, the
yTable contains dependent values, first derivatives, and second derivatives.outputOrder - The number of derivatives to return. To return just the dependent variable values,
pass 0 for this parameter. To return the first derivatives along with the dependent variable values,
pass 1. To retrieve the second derivatives as well, pass 2. Note that not all interpolation algorithms are capable
of returning second derivative information, and if a higher outputOrder
is requested than the algorithm is able to provide, the highest order derivative
will be returned and the request for the higher order derivatives is ignored.startIndex - The index in xTable of the first value to use in the interpolation.
The index of the first value in yTable to use is calculated as:
* * ( + 1)length - The number of values to use in the interpolation. This value should be one more than the
desired interpolation degree. For example for 7th degree interpolation, this parameter
should be 8.yStride elements,
each of which is an interpolated dependent variable value. If outputOrder
is greater than zero, the array contains an additional number of yStride elements,
for each output order.ArgumentNullException - Thrown when xTable or yTable is null.@Nonnull public final double[] interpolateWithDegree(double x, @Nonnull double[] xTable, @Nonnull double[] yTable, int degree, int yStride, int inputOrder, int outputOrder)
degree.
The xTable array can contain any number of elements, and the appropriate subset
will be selected according to the degree of interpolation requested. For
example, if degree is 5, the 6 elements surrounding x
will be used for interpolation. When using LinearApproximation, the degree should be 1
since it always deals with only 2 elements surrounding x.
The yTable array should contain a number of elements equal to:
* * ( + 1) If insufficient elements are provided
to perform the requested degree of interpolation, the highest possible degree of interpolation
will be performed.
x - The independent variable for which the dependent variables will be interpolated.xTable - The array of independent variables to use to interpolate. The values
in this array must be in increasing order and the same value must not occur twice in the array.yTable - The array of dependent variables to use to interpolate. For a set of three
dependent values (p,q,w) and their derivatives (dp, dq, dw) at time 1 and time 2 this should be
as follows: {p1, q1, w1, dp1, dq1, dw1, p2, q2, w2, dp2, dq2, dw2}.degree - The degree of interpolation to perform. For Linear Interpolation, this value should be 1.yStride - The number of dependent variable values in yTable corresponding to
each independent variable value in xTable. If inputOrder
is greater than 0, this is also the number of first derivative values, second derivative
values, etc. corresponding to each value in xTable.inputOrder - The number of dependent variable derivatives in yTable. If this value is 0,
the yTable is assumed to contain only dependent variable values, with each
yStride of them corresponding to a single independent variable in the
xTable. If this value is 1, the yTable is assumed to
contain not only the dependent variable values but also their derivatives. There are
yStride dependent variable values followed by yStride
dependent variable first derivatives corresponding to each independent variable value
in xTable. Similarly, if this value is 2, the
yTable contains values, first derivatives, and second derivatives.outputOrder - The number of derivatives to return. To return just the dependent variable values,
pass 0 for this parameter. To return the first derivatives as well, pass 1. To retrieve the
second derivatives as well, pass 2. Note that not all interpolation algorithms are capable
of returning second derivative information, and if a higher outputOrder
is requested than the algorithm is able to provide, the highest order derivative
will be returned and the request for the higher order derivatives is ignored.yStride elements,
each of which is an interpolated dependent variable value. If outputOrder
is 1 or greater, the array contains an additional yStride elements,
each of which is an interpolated dependent variable first derivative. Lastly, if
outputOrder is 2 or greater, the array contains another additional
yStride elements, each of which is an interpolated variable second
derivative.