cc.redberry.core.context

Class Context

java.lang.Object

cc.redberry.core.context.Context

public final class Context
extends java.lang.Object

This class represents Redberry context. It stores all Redberry session data (in some sense it stores static data).

Management of current Redberry context is made through ContextManager class. Context of Redberry is attached to the current thread, so that any thread created from the outside of Redebrry will hold a unique instance of Context object. In such a way tensors created in one thread can not be used in the other thread because they are in some sense "attached" to the initial thread. However, if thread is created through the executor service which is obtained from ContextManager.getExecutorService(), it will share the same context as initial thread (such threads could hold concurrent computations regarding single context, the appropriate synchronization is assumed). In order to create a new session of Redberry with a particular context, an instance of this class should be set as a current context via ContextManager.setCurrentContext(Context).

Since:

1.0

See Also:

NameManager, IndexConverterManager, ParseManager, OutputFormat, ContextManager, ContextSettings

Constructor Summary

Constructors

Constructor and Description
Context(ContextSettings contextSettings) Creates context from the settings

Method Summary

Modifier and Type	Method and Description
SimpleTensor	createKronecker(int index1, int index2) Returns Kronecker tensor with specified upper and lower indices.
SimpleTensor	createMetric(int index1, int index2) Returns metric tensor with specified indices.
SimpleTensor	createMetricOrKronecker(int index1, int index2) Returns metric tensor if specified indices have same states and Kronecker tensor if specified indices have different states.
SimpleTensor	generateNewSymbol() Generates a new symbol which never used before during current session.
static Context	get() Returns the current context of Redberry session.
OutputFormat	getDefaultOutputFormat() Returns current default output format.
OutputPort<SimpleTensor>	getDefaultParametersGenerator() Return output port which generates new symbol via generateNewSymbol() at each take() invocation.
IndexConverterManager	getIndexConverterManager() Returns index converter manager of current session.
java.lang.String	getKroneckerName() Returns string representation of Kronecker delta name
java.util.Set<IndexType>	getMatrixTypes() Returns all matrix types.
java.lang.String	getMetricName() Returns string representation of metric tensor name
java.util.Set<IndexType>	getMetricTypes() Returns all metric types.
NameDescriptor	getNameDescriptor(int nameId) Returns NameDescriptor corresponding to the specified int nameId.
NameManager	getNameManager() Returns the name manager (namespace) of current session.
ParseManager	getParseManager() Returns parse manager of current session
org.apache.commons.math3.random.RandomGenerator	getRandomGenerator() Returns random generator used by Redberry in current session.
boolean	isKronecker(SimpleTensor t) Returns true if specified tensor is a Kronecker tensor
boolean	isKroneckerOrMetric(SimpleTensor t) Returns true if specified tensor is a metric or a Kronecker tensor
boolean	isMetric(byte type) Returns true if metric is defined for the specified index type.
boolean	isMetric(SimpleTensor t) Returns true if specified tensor is a metric tensor
void	resetTensorNames() This method resets all tensor names in the namespace.
void	resetTensorNames(long seed) This method resets all tensor names in the namespace and sets a specified seed to the NameManager.
void	setDefaultOutputFormat(OutputFormat defaultOutputFormat) Sets the default output format.
void	setKroneckerName(java.lang.String name) Sets the default Kronecker tensor name.
void	setMetricName(java.lang.String name) Sets the default metric tensor name.

Methods inherited from class java.lang.Object

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

Constructor Detail

Context

public Context(ContextSettings contextSettings)

Creates context from the settings

Parameters:

contextSettings - settings

See Also:

ContextSettings

Method Detail

getMetricTypes

public java.util.Set<IndexType> getMetricTypes()

Returns all metric types.

Returns:

all metric types

getMatrixTypes

public java.util.Set<IndexType> getMatrixTypes()

Returns all matrix types.

Returns:

all matrix types

resetTensorNames

public void resetTensorNames()

This method resets all tensor names in the namespace.

Any tensor created before this method call becomes invalid, and must not be used! This method is mainly used in unit tests, so avoid invocations of this method in general computations.

resetTensorNames

public void resetTensorNames(long seed)

This method resets all tensor names in the namespace and sets a specified seed to the NameManager. If this method is invoked with constant seed before any interactions with Redberry, further behaviour of Redberry will be fully deterministic from run to run (order of summands and multipliers will be fixed, computation time will be pretty constant, hash codes will be the same).

Any tensor created before this method call becomes invalid, and must not be used! This method is mainly used in unit tests, so avoid invocations of this method in general computations.

setDefaultOutputFormat

public void setDefaultOutputFormat(OutputFormat defaultOutputFormat)

Sets the default output format. After this step, all expressions will be printed according to the specified output format.

Parameters:

defaultOutputFormat - output format

getDefaultOutputFormat

public OutputFormat getDefaultOutputFormat()

Returns current default output format.

Returns:

current default output format

getIndexConverterManager

public IndexConverterManager getIndexConverterManager()

Returns index converter manager of current session.

Returns:

index converter manager of current session

getNameManager

public NameManager getNameManager()

Returns the name manager (namespace) of current session.

Returns:

the name manager (namespace) of current session.

getNameDescriptor

public NameDescriptor getNameDescriptor(int nameId)

Returns NameDescriptor corresponding to the specified int nameId.

Parameters:

nameId - integer name of tensor

Returns:

corresponding NameDescriptor

getKroneckerName

public java.lang.String getKroneckerName()

Returns string representation of Kronecker delta name

Returns:

string representation of Kronecker delta name

getMetricName

public java.lang.String getMetricName()

Returns string representation of metric tensor name

Returns:

string representation of metric tensor name

setMetricName

public void setMetricName(java.lang.String name)

Sets the default metric tensor name. After this step, metric tensor will be printed with the specified string name.

Parameters:

name - string representation of metric tensor name

setKroneckerName

public void setKroneckerName(java.lang.String name)

Sets the default Kronecker tensor name. After this step, Kronecker tensor will be printed with the specified string name.

Parameters:

name - string representation of Kronecker tensor name

isKronecker

public boolean isKronecker(SimpleTensor t)

Returns true if specified tensor is a Kronecker tensor

Parameters:

t - tensor

Returns:

true if specified tensor is a Kronecker tensor

isMetric

public boolean isMetric(SimpleTensor t)

Returns true if specified tensor is a metric tensor

Parameters:

t - tensor

Returns:

true if specified tensor is a metric tensor

isKroneckerOrMetric

public boolean isKroneckerOrMetric(SimpleTensor t)

Returns true if specified tensor is a metric or a Kronecker tensor

Parameters:

t - tensor

Returns:

true if specified tensor is a metric or a Kronecker tensor

getParseManager

public ParseManager getParseManager()

Returns parse manager of current session

Returns:

parse manager of current session

isMetric

public boolean isMetric(byte type)

Returns true if metric is defined for the specified index type.

Parameters:

type - index type

Returns:

true if metric is defined for the specified index type

createKronecker

public SimpleTensor createKronecker(int index1,
                                    int index2)

Returns Kronecker tensor with specified upper and lower indices.

Parameters:

index1 - first index

index2 - second index

Returns:

Kronecker tensor with specified upper and lower indices

Throws:

java.lang.IllegalArgumentException - if indices have same states

java.lang.IllegalArgumentException - if indices have different types

createMetric

public SimpleTensor createMetric(int index1,
                                 int index2)

Returns metric tensor with specified indices.

Parameters:

index1 - first index

index2 - second index

Returns:

metric tensor with specified indices

Throws:

java.lang.IllegalArgumentException - if indices have different states

java.lang.IllegalArgumentException - if indices have different types

java.lang.IllegalArgumentException - if indices have non metric types

createMetricOrKronecker

public SimpleTensor createMetricOrKronecker(int index1,
                                            int index2)

Returns metric tensor if specified indices have same states and Kronecker tensor if specified indices have different states.

Parameters:

index1 - first index

index2 - second index

Returns:

metric tensor if specified indices have same states and Kronecker tensor if specified indices have different states

Throws:

java.lang.IllegalArgumentException - if indices have different types

java.lang.IllegalArgumentException - if indices have same states and non metric types

generateNewSymbol

public SimpleTensor generateNewSymbol()

Generates a new symbol which never used before during current session.

Returns:

new symbol which never used before during current session

getDefaultParametersGenerator

public OutputPort<SimpleTensor> getDefaultParametersGenerator()

Return output port which generates new symbol via generateNewSymbol() at each take() invocation.

Returns:

output port which generates new symbol via generateNewSymbol() at each take() invocation.

getRandomGenerator

public org.apache.commons.math3.random.RandomGenerator getRandomGenerator()

Returns random generator used by Redberry in current session.

Returns:

random generator used by Redberry in current session

get

public static Context get()

Returns the current context of Redberry session.

Returns:

the current context of Redberry session.