Requires an estimate for the initial neutron energy which it uses to search for monitor peaks and from these calculate an accurate energy. More...

#include <GetEi.h>

Inheritance diagram for Mantid::Algorithms::GetEi:

Public Member Functions
const std::string	category () const override
	Algorithm's category for identification overriding a virtual method.

	GetEi ()
	Empty default constructor algorithm() calls the constructor in the base class.

const std::string	name () const override
	Algorithm's name for identification overriding a virtual method.

const std::string	summary () const override
	Summary of algorithms purpose.

int	version () const override
	Algorithm's version for identification overriding a virtual method.

Public Member Functions inherited from Mantid::API::Algorithm
	Algorithm ()
	Constructor.

	Algorithm (const Algorithm &)=delete

Algorithm &	operator= (const Algorithm &)=delete

	~Algorithm () override
	Virtual destructor.

void	initialize () override
	Initialization method invoked by the framework.

bool	execute () override final
	The actions to be performed by the algorithm on a dataset.

void	addTimer (const std::string &name, const Kernel::time_point_ns &begin, const Kernel::time_point_ns &end)

void	executeAsChildAlg () override
	Execute as a Child Algorithm.

std::map< std::string, std::string >	validateInputs () override
	Perform validation of ALL the input properties of the algorithm.

ExecutionState	executionState () const override
	Gets the current execution state.

ResultState	resultState () const override
	Gets the current result State.

bool	isInitialized () const override
	Has the Algorithm already been initialized.

bool	isExecuted () const override
	Has the Algorithm already been executed successfully.

bool	isRunning () const override
	True if the algorithm is running.

bool	isReadyForGarbageCollection () const override
	True if the algorithm is ready for garbage collection.

bool	isChild () const override
	To query whether algorithm is a child.

void	setChild (const bool isChild) override
	To set whether algorithm is a child.

void	enableHistoryRecordingForChild (const bool on) override
	Change the state of the history recording flag.

bool	isRecordingHistoryForChild ()

void	setAlwaysStoreInADS (const bool doStore) override
	Do we ALWAYS store in the AnalysisDataService? This is set to true for python algorithms' child algorithms.

bool	getAlwaysStoreInADS () const override
	Returns true if we always store in the AnalysisDataService.

void	setRethrows (const bool rethrow) override
	Set whether the algorithm will rethrow exceptions.

Poco::ActiveResult< bool >	executeAsync () override
	Asynchronous execution.

void	addObserver (const Poco::AbstractObserver &observer) const override
	Add an observer for a notification.

void	removeObserver (const Poco::AbstractObserver &observer) const override
	Remove an observer.

void	cancel () override
	Raises the cancel flag.

bool	getCancel () const
	Returns the cancellation state.

Kernel::Logger &	getLogger () const
	Returns a reference to the logger.

void	setLogging (const bool value) override
	Logging can be disabled by passing a value of false.

bool	isLogging () const override
	returns the status of logging, True = enabled

void	setLoggingOffset (const int value) override
	gets the logging priority offset

int	getLoggingOffset () const override
	returns the logging priority offset

void	setAlgStartupLogging (const bool enabled) override
	disable Logging of start and end messages

bool	getAlgStartupLogging () const override
	get the state of Logging of start and end messages

void	setChildStartProgress (const double startProgress) const override
	setting the child start progress

void	setChildEndProgress (const double endProgress) const override
	setting the child end progress

std::string	toString () const override
	Serialize an object to a string.

::Json::Value	toJson () const override
	Serialize an object to a json object.

virtual std::shared_ptr< Algorithm >	createChildAlgorithm (const std::string &name, const double startProgress=-1., const double endProgress=-1., const bool enableLogging=true, const int &version=-1)
	Create a Child Algorithm.

void	setupAsChildAlgorithm (const Algorithm_sptr &algorithm, const double startProgress=-1., const double endProgress=-1., const bool enableLogging=true)
	Setup algorithm as child algorithm.

void	trackAlgorithmHistory (std::shared_ptr< AlgorithmHistory > parentHist)
	set whether we wish to track the child algorithm's history and pass it the parent object to fill.

void	findWorkspaces (WorkspaceVector &workspaces, unsigned int direction, bool checkADS=false) const
	Populate lists of the workspace properties for a given direction (InOut workspaces are included in both input/output)

virtual bool	checkGroups ()
	Check the input workspace properties for groups.

virtual bool	processGroups ()
	Process WorkspaceGroup inputs.

void	copyNonWorkspaceProperties (IAlgorithm *alg, int periodNum)
	Copy all the non-workspace properties from this to alg.

void	declareProperty (std::unique_ptr< Kernel::Property > p, const std::string &doc="") override
	Add a property to the list of managed properties.

void	declareOrReplaceProperty (std::unique_ptr< Kernel::Property > p, const std::string &doc="") override
	Add or replace property in the list of managed properties.

void	resetProperties () override
	Reset property values back to initial values (blank or default values)

void	setProperties (const std::string &propertiesJson, const std::unordered_set< std::string > &ignoreProperties=std::unordered_set< std::string >(), bool createMissing=false) override
	Set the ordered list of properties by one string of values, separated by semicolons.

void	setProperties (const ::Json::Value &jsonValue, const std::unordered_set< std::string > &ignoreProperties=std::unordered_set< std::string >(), bool createMissing=false) override
	Sets all the declared properties from a json object.

void	setPropertiesWithString (const std::string &propertiesString, const std::unordered_set< std::string > &ignoreProperties=std::unordered_set< std::string >()) override
	Sets all the declared properties from a string.

void	setPropertyValue (const std::string &name, const std::string &value) override
	Set the value of a property by string N.B.

void	setPropertyValueFromJson (const std::string &name, const Json::Value &value) override
	Set the value of a property by Json::Value object.

void	setPropertyOrdinal (const int &index, const std::string &value) override
	Set the value of a property by an index N.B.

virtual void	copyPropertiesFrom (const Algorithm &alg)
	Make m_properties point to the same PropertyManager as alg.m_properties.

bool	existsProperty (const std::string &name) const override
	Checks whether the named property is already in the list of managed property.

bool	validateProperties () const override
	Validates all the properties in the collection.

size_t	propertyCount () const override
	Count the number of properties under management.

std::string	getPropertyValue (const std::string &name) const override
	Get the value of a property as a string.

const std::vector< Kernel::Property * > &	getProperties () const override
	Get the list of managed properties.

std::vector< std::string >	getDeclaredPropertyNames () const noexcept override
	Return the list of declared property names.

TypedValue	getProperty (const std::string &name) const override
	Get the value of a property.

std::string	asString (bool withDefaultValues=false) const override
	Return the property manager serialized as a string.

::Json::Value	asJson (bool withDefaultValues=false) const override
	Return the property manager serialized as a json object.

bool	isDefault (const std::string &name) const

void	removeProperty (const std::string &name, const bool delproperty=true) override
	Removes the property from management.

std::unique_ptr< Kernel::Property >	takeProperty (const size_t index) override
	Removes the property from management and returns a pointer to it.

void	clear () override
	Clears all properties under management.

void	afterPropertySet (const std::string &) override
	Override this method to perform a custom action right after a property was set.

Kernel::Property *	getPointerToProperty (const std::string &name) const override
	Get a property by name.

Kernel::Property *	getPointerToPropertyOrdinal (const int &index) const override
	Get a property by an index.

virtual void	declareProperty (std::unique_ptr< Property > p, const std::string &doc="")=0
	Function to declare properties (i.e. store them)

template<typename T >
void	declareProperty (const std::string &name, T value, IValidator_sptr validator=std::make_shared< NullValidator >(), const std::string &doc="", const unsigned int direction=Direction::Input)
	Add a property of the template type to the list of managed properties.

template<typename T >
void	declareProperty (const std::string &name, T value, const std::string &doc, const unsigned int direction=Direction::Input)
	Add a property to the list of managed properties with no validator.

template<typename T >
void	declareProperty (const std::string &name, T value, const unsigned int direction)
	Add a property of the template type to the list of managed properties.

void	declareProperty (const std::string &name, const char *value, IValidator_sptr validator=std::make_shared< NullValidator >(), const std::string &doc=std::string(), const unsigned int direction=Direction::Input)
	Specialised version of declareProperty template method to prevent the creation of a PropertyWithValue of type const char* if an argument in quotes is passed (it will be converted to a string).

void	declareProperty (const std::string &name, const char *value, const std::string &doc, IValidator_sptr validator=std::make_shared< NullValidator >(), const unsigned int direction=Direction::Input)
	Specialised version of declareProperty template method to prevent the creation of a PropertyWithValue of type const char* if an argument in quotes is passed (it will be converted to a string).

void	declareProperty (const std::string &name, const char *value, const unsigned int direction)
	Add a property of string type to the list of managed properties.

const std::string	category () const override
	function to return a category of the algorithm.

const std::vector< std::string >	categories () const override
	Function to return all of the categories that contain this algorithm.

const std::string	categorySeparator () const override
	Function to return the separator token for the category string.

const std::vector< std::string >	seeAlso () const override
	Function to return all of the seeAlso (these are not validated) algorithms related to this algorithm.A default implementation is provided.

const std::string	alias () const override
	function to return any aliases to the algorithm; A default implementation is provided

const std::string	aliasDeprecated () const override
	Expiration date (in ISO8601 format) for the algorithm aliases; default implementation for no expiration date.

const std::string	helpURL () const override
	function to return URL for algorithm documentation; A default implementation is provided.

template<typename T , typename = typename std::enable_if<std::is_convertible<T , MatrixWorkspace >::value>::type>
std::tuple< std::shared_ptr< T >, Indexing::SpectrumIndexSet >	getWorkspaceAndIndices (const std::string &name) const
	Mechanism for retriving the index property.

template<typename T1 , typename T2 , typename = typename std::enable_if<std::is_convertible<T1 , MatrixWorkspace >::value>::type, typename = typename std::enable_if<std::is_convertible<T2 , std::string >::value \|\| std::is_convertible<T2 , std::vector<int64_t> >::value>::type>
void	setWorkspaceInputProperties (const std::string &name, const std::shared_ptr< T1 > &wksp, IndexType type, const T2 &list)
	Mechanism for setting the index property with a workspace shared pointer.

template<typename T1 , typename T2 , typename = typename std::enable_if<std::is_convertible<T1 , MatrixWorkspace >::value>::type, typename = typename std::enable_if<std::is_convertible<T2 , std::string >::value \|\| std::is_convertible<T2 , std::vector<int64_t> >::value>::type>
void	setWorkspaceInputProperties (const std::string &name, const std::string &wsName, IndexType type, const T2 &list)
	Mechanism for setting the index property with a workspace shared pointer.

const std::string	workspaceMethodName () const override

const std::vector< std::string >	workspaceMethodOn () const override

const std::string	workspaceMethodInputProperty () const override

AlgorithmID	getAlgorithmID () const override
	Algorithm ID.

Algorithms As Methods
Public Member Functions inherited from Mantid::Kernel::IPropertyManager
void	declareProperty (const std::string &name, const char *value, const std::string &doc, IValidator_sptr validator=std::make_shared< NullValidator >(), const unsigned int direction=Direction::Input)
	Specialised version of declareProperty template method to prevent the creation of a PropertyWithValue of type const char* if an argument in quotes is passed (it will be converted to a string).

void	declareProperty (const std::string &name, const char *value, const unsigned int direction)
	Add a property of string type to the list of managed properties.

void	declareProperty (const std::string &name, const char *value, IValidator_sptr validator=std::make_shared< NullValidator >(), const std::string &doc=std::string(), const unsigned int direction=Direction::Input)
	Specialised version of declareProperty template method to prevent the creation of a PropertyWithValue of type const char* if an argument in quotes is passed (it will be converted to a string).

template<typename T >
void	declareProperty (const std::string &name, T value, const std::string &doc, const unsigned int direction=Direction::Input)
	Add a property to the list of managed properties with no validator.

template<typename T >
void	declareProperty (const std::string &name, T value, const unsigned int direction)
	Add a property of the template type to the list of managed properties.

template<typename T >
void	declareProperty (const std::string &name, T value, IValidator_sptr validator=std::make_shared< NullValidator >(), const std::string &doc="", const unsigned int direction=Direction::Input)
	Add a property of the template type to the list of managed properties.

virtual void	filterByProperty (Mantid::Kernel::LogFilter *, const std::vector< std::string > &)

std::vector< Property * >	getPropertiesInGroup (const std::string &group) const
	Get the list of managed properties in a given group.

IPropertyManager *	setProperty (const std::string &name, const char *value)
	Specialised version of setProperty template method to handle const char *.

IPropertyManager *	setProperty (const std::string &name, const std::string &value)
	Specialised version of setProperty template method to handle std::string.

template<typename T >
IPropertyManager *	setProperty (const std::string &name, const T &value)
	Templated method to set the value of a PropertyWithValue.

template<typename T >
IPropertyManager *	setProperty (const std::string &name, std::unique_ptr< T > value)
	Templated method to set the value of a PropertyWithValue from a std::unique_ptr.

void	setPropertyGroup (const std::string &name, const std::string &group)
	Set the group for a given property.

void	setPropertySettings (const std::string &name, std::unique_ptr< IPropertySettings > settings)

void	updatePropertyValues (const IPropertyManager &other)
	Update values of the existing properties.

virtual	~IPropertyManager ()=default

Private Types
enum	direction { GO_LEFT = -1 , GO_RIGHT = 1 }
	used by the function findHalfLoc to indicate whether to search left or right More...

Private Member Functions
void	advanceProgress (double toAdd)
	Update the percentage complete estimate assuming that the algorithm has completed a task with estimated RunTime toAdd.

void	exec () override
	Executes the algorithm.

void	extractSpec (int wsInd, double start, double end)
	Calls CropWorkspace as a Child Algorithm and passes to it the InputWorkspace property.

double	findHalfLoc (MantidVec::size_type startInd, const double height, const double noise, const direction go) const
	Estimates the closest time, looking either or back, when the number of counts is half that in the bin whose index that passed.

void	getGeometry (const API::MatrixWorkspace_const_sptr &WS, specnum_t mon0Spec, specnum_t mon1Spec, double &monitor0Dist, double &monitor1Dist) const
	Gets the distances between the source and detectors whose IDs you pass to it.

std::vector< size_t >	getMonitorWsIndexs (const API::MatrixWorkspace_const_sptr &WS, specnum_t specNum1, specnum_t specNum2) const
	Converts detector IDs to spectra indexes.

double	getPeakCentre (const API::MatrixWorkspace_const_sptr &WS, const size_t monitIn, const double peakTime)
	Looks for and examines a peak close to that specified by the input parameters and examines it to find a representative time for when the neutrons hit the detector.

void	getPeakEstimates (double &height, int64_t &centreInd, double &background) const
	Finds the largest peak by looping through the histogram and finding the maximum value.

void	init () override
	Virtual method - must be overridden by concrete algorithm.

double	neutron_E_At (double speed) const
	Get the kinetic energy of a neuton in joules given it speed using E=mv^2/2.

double	timeToFly (double s, double E_KE) const
	Uses E_KE = mv^2/2 and s = vt to calculate the time required for a neutron to travel a distance, s.

Private Attributes
double	m_fracCompl
	An estimate of the percentage of the algorithm runtimes that has been completed.

API::MatrixWorkspace_sptr	m_tempWS
	name of the tempory workspace that we create and use

Static Private Attributes
static const double	CROP = 0.15
	fraction of algorithm time taken up with running CropWorkspace

static const double	FIT_PEAK = 0.2
	single call to ConvertToDistribution

static const double	GET_COUNT_RATE = 0.15
	fraction of algorithm taken by a

static const double	HALF_WINDOW = 8.0 / 100
	the range of TOF X-values over which the peak will be searched is double this value, i.e.

static const double	PEAK_THRESH_A = 5.0
	ignore peaks where the half width times the ratio of the peak height to the background is less this

static const double	PEAK_THRESH_H = 3.0
	ignore an peaks that are less than this factor of the background

static const int64_t	PEAK_THRESH_W = 3
	for peaks where the distance to the half heigth is less than this number of bins in either direction e.g.

Additional Inherited Members
Public Types inherited from Mantid::API::Algorithm
using	WorkspaceVector = std::vector< std::shared_ptr< Workspace > >

Static Public Member Functions inherited from Mantid::API::Algorithm
static IAlgorithm_sptr	fromString (const std::string &input)
	De-serialize an object from a string.

static IAlgorithm_sptr	fromJson (const Json::Value &input)
	De-serialize an object from a Json.

static IAlgorithm_sptr	fromHistory (const AlgorithmHistory &history)
	Construct an object from a history entry.

Public Attributes inherited from Mantid::API::Algorithm
bool	calledByAlias = false
	Flag to indicate if the algorithm is called by its alias.

Protected Member Functions inherited from Mantid::API::Algorithm
virtual const std::string	workspaceMethodOnTypes () const
	Returns a semi-colon separated list of workspace types to attach this algorithm.

void	cacheWorkspaceProperties ()
	Go through the properties and cache the input/output workspace properties for later use.

void	cacheInputWorkspaceHistories ()
	Cache the histories of any input workspaces so they can be copied over after algorithm completion.

void	setExecutionState (const ExecutionState state)
	Sets the current execution state.

void	setResultState (const ResultState state)
	Sets the result execution state.

void	store ()
	Stores any output workspaces into the AnalysisDataService.

void	progress (double p, const std::string &msg="", double estimatedTime=0.0, int progressPrecision=0)
	Sends ProgressNotification.

void	interruption_point ()
	This is called during long-running operations, and check if the algorithm has requested that it be cancelled.

Poco::NotificationCenter &	notificationCenter () const
	Return a reference to the algorithm's notification dispatcher.

void	handleChildProgressNotification (const Poco::AutoPtr< ProgressNotification > &pNf)
	Observation slot for child algorithm progress notification messages, these are scaled and then signalled for this algorithm.

const Poco::AbstractObserver &	progressObserver () const
	Return a reference to the algorithm's object that is reporting progress.

bool	isWorkspaceProperty (const Kernel::Property *const prop) const
	checks the property is a workspace property

bool	trackingHistory ()
	get whether we are tracking the history for this algorithm,

virtual void	fillHistory ()
	Copy workspace history from input workspaces to output workspaces and record the history for ths algorithm.

void	fillHistory (const std::vector< Workspace_sptr > &outputWorkspaces)
	Copy workspace history from input workspaces to provided vector of output workspaces.

virtual void	setOtherProperties (IAlgorithm *alg, const std::string &propertyName, const std::string &propertyValue, int periodNum)
	Virtual method to set the non workspace properties for this algorithm.

template<typename T , const int AllowedIndexTypes = static_cast<int>(IndexType::WorkspaceIndex), typename... WSPropArgs, typename = typename std::enable_if<std::is_convertible<T , MatrixWorkspace >::value>::type>
void	declareWorkspaceInputProperties (const std::string &propertyName, const std::string &doc, WSPropArgs &&...wsPropArgs)
	Declare a property which defines the workspace and allowed index types, as well as a property for capturing the indices all at once.

Protected Member Functions inherited from Mantid::Kernel::IPropertyManager
template<typename T >
T	getValue (const std::string &name) const
	Templated method to get the value of a property.

template<>
MANTID_KERNEL_DLL PropertyManager_sptr	getValue (const std::string &name) const

template<>
MANTID_KERNEL_DLL PropertyManager_const_sptr	getValue (const std::string &name) const

Static Protected Member Functions inherited from Mantid::API::Algorithm
template<typename NumT >
static bool	isEmpty (const NumT toCheck)
	checks that the value was not set by users, uses the value in empty double/int.

Protected Attributes inherited from Mantid::API::Algorithm
std::atomic< bool >	m_cancel
	Set to true to stop execution.

std::atomic< bool >	m_parallelException
	Set if an exception is thrown, and not caught, within a parallel region.

std::vector< IWorkspaceProperty * >	m_inputWorkspaceProps
	All the WorkspaceProperties that are Input or InOut. Set in execute()

std::shared_ptr< AlgorithmHistory >	m_history
	Pointer to the history for the algorithm being executed.

Kernel::Logger	m_log
	Logger for this algorithm.

Kernel::Logger &	g_log

std::shared_ptr< AlgorithmHistory >	m_parentHistory
	Pointer to the parent history object (if set)

std::vector< WorkspaceVector >	m_unrolledInputWorkspaces
	One vector of workspaces for each input workspace property.

size_t	m_groupSize
	Size of the group(s) being processed.

bool	m_usingBaseProcessGroups = false
	distinguish between base processGroups() and overriden/algorithm specific versions

Static Protected Attributes inherited from Mantid::API::Algorithm
static size_t	g_execCount = 0
	Counter to keep track of algorithm execution order.

Detailed Description

Requires an estimate for the initial neutron energy which it uses to search for monitor peaks and from these calculate an accurate energy.

Required Properties:

InputWorkspace - The X units of this workspace must be time of flight with times in micro-seconds
Monitor1ID - The detector ID of the first monitor
Monitor2ID - The detector ID of the second monitor
EnergyEstimate - An approximate value for the typical incident energy, energy of neutrons leaving the source (meV)
IncidentEnergy - The calculated energy

Author: Steve Williams ISIS Rutherford Appleton Laboratory & NScD Oak Ridge National Laboratory

Date: 27/07/2009

Definition at line 37 of file GetEi.h.

Member Enumeration Documentation

◆ direction

enum Mantid::Algorithms::GetEi::direction

private

used by the function findHalfLoc to indicate whether to search left or right

Enumerator
GO_LEFT	flag value to serch left
GO_RIGHT	flag value to search right

Definition at line 62 of file GetEi.h.

Constructor & Destructor Documentation

◆ GetEi()

Mantid::Algorithms::GetEi::GetEi ( )

Empty default constructor algorithm() calls the constructor in the base class.

Definition at line 47 of file GetEi.cpp.

Member Function Documentation

◆ advanceProgress()

void Mantid::Algorithms::GetEi::advanceProgress ( double toAdd )

private

Update the percentage complete estimate assuming that the algorithm has completed a task with estimated RunTime toAdd.

Definition at line 464 of file GetEi.cpp.

References Mantid::API::Algorithm::interruption_point(), m_fracCompl, and Mantid::API::Algorithm::progress().

Referenced by getPeakCentre().

◆ category()

const std::string Mantid::Algorithms::GetEi::category ( ) const

inlineoverridevirtual

Algorithm's category for identification overriding a virtual method.

Implements Mantid::API::IAlgorithm.

Definition at line 52 of file GetEi.h.

◆ exec()

void Mantid::Algorithms::GetEi::exec ( )

overrideprivatevirtual

Executes the algorithm.

Exceptions

out_of_range	if the peak runs off the edge of the histogram
NotFoundError	if one of the requested spectrum numbers was not found in the workspace
IndexError	if there is a problem converting spectra indexes to spectra numbers, which would imply there is a problem with the workspace
invalid_argument	if a good peak fit wasn't made or the input workspace does not have common binning

Implements Mantid::API::Algorithm.

Definition at line 86 of file GetEi.cpp.

References Mantid::API::Algorithm::g_log, getGeometry(), getMonitorWsIndexs(), getPeakCentre(), Mantid::API::Algorithm::getProperty(), HALF_WINDOW, Mantid::Kernel::Logger::information(), Mantid::Kernel::Direction::Input, Mantid::PhysicalConstants::meV, neutron_E_At(), Mantid::Kernel::Logger::notice(), Mantid::Kernel::IPropertyManager::setProperty(), and timeToFly().

◆ extractSpec()

void Mantid::Algorithms::GetEi::extractSpec	(	int	wsInd,
		double	start,
		double	end
	)

private

Calls CropWorkspace as a Child Algorithm and passes to it the InputWorkspace property.

Parameters

wsInd	:: the index number of the histogram to extract
start	:: the number of the first bin to include (starts counting bins at 0)
end	:: the number of the last bin to include (starts counting bins at 0)

Exceptions

out_of_range	if start, end or wsInd are set outside of the valid range for the workspace
runtime_error	if the algorithm just falls over
invalid_argument	if the input workspace does not have common binning

Definition at line 317 of file GetEi.cpp.

References Mantid::API::Algorithm::createChildAlgorithm(), CROP, Mantid::API::Algorithm::getProperty(), Mantid::API::Algorithm::interruption_point(), m_fracCompl, m_tempWS, and Mantid::API::Algorithm::progress().

Referenced by getPeakCentre().

◆ findHalfLoc()

double Mantid::Algorithms::GetEi::findHalfLoc	(	MantidVec::size_type	startInd,
		const double	height,
		const double	noise,
		const direction	go
	)		const

private

Estimates the closest time, looking either or back, when the number of counts is half that in the bin whose index that passed.

Parameters

startInd	:: index of the bin to search around, e.g. the index of the peak centre
height	:: the number of counts (or count rate) to compare against e.g. a peak height
noise	:: mean number of counts in each bin in the workspace
go	:: either GetEi::GO_LEFT or GetEi::GO_RIGHT

Returns: estimated TOF of the half maximum point

Exceptions

out_of_range	if the end of the histogram is reached before the point is found
invalid_argument	if the peak is too thin

Definition at line 392 of file GetEi.cpp.

References Mantid::Kernel::Logger::debug(), Mantid::Kernel::Logger::error(), Mantid::API::Algorithm::g_log, HALF_WINDOW, height, m_tempWS, PEAK_THRESH_A, PEAK_THRESH_W, Mantid::Geometry::X, and Mantid::Geometry::Y.

Referenced by getPeakCentre().

◆ getGeometry()

void Mantid::Algorithms::GetEi::getGeometry	(	const API::MatrixWorkspace_const_sptr &	WS,
		specnum_t	mon0Spec,
		specnum_t	mon1Spec,
		double &	monitor0Dist,
		double &	monitor1Dist
	)		const

private

Gets the distances between the source and detectors whose IDs you pass to it.

Parameters

WS	:: the input workspace
mon0Spec	:: Spectrum number of the output from the first monitor
mon1Spec	:: Spectrum number of the output from the second monitor
monitor0Dist	:: the calculated distance to the detector whose ID was passed to this function first
monitor1Dist	:: calculated distance to the detector whose ID was passed to this function second

Exceptions

NotFoundError if no detector is found for the detector ID given

Definition at line 149 of file GetEi.cpp.

References Mantid::Kernel::Logger::error(), and Mantid::API::Algorithm::g_log.

Referenced by exec().

◆ getMonitorWsIndexs()

std::vector< size_t > Mantid::Algorithms::GetEi::getMonitorWsIndexs	(	const API::MatrixWorkspace_const_sptr &	WS,
		specnum_t	specNum1,
		specnum_t	specNum2
	)		const

private

Converts detector IDs to spectra indexes.

Parameters

WS	:: the workspace on which the calculations are being performed
specNum1	:: spectrum number of the output of the first monitor
specNum2	:: spectrum number of the output of the second monitor

Returns: the indexes of the histograms created by the detector whose ID were passed

Exceptions

NotFoundError if one of the requested spectrum numbers was not found in the workspace

Definition at line 201 of file GetEi.cpp.

References Mantid::Kernel::Logger::error(), and Mantid::API::Algorithm::g_log.

Referenced by exec().

◆ getPeakCentre()

double Mantid::Algorithms::GetEi::getPeakCentre	(	const API::MatrixWorkspace_const_sptr &	WS,
		const size_t	monitIn,
		const double	peakTime
	)

private

Looks for and examines a peak close to that specified by the input parameters and examines it to find a representative time for when the neutrons hit the detector.

Parameters

WS	:: the workspace containing the monitor spectrum
monitIn	:: the index of the histogram that contains the monitor spectrum
peakTime	:: the estimated TOF of the monitor peak in the time units of the workspace

Returns: a time of flight value in the peak in microseconds

Exceptions

invalid_argument	if a good peak fit wasn't made or the input workspace does not have common binning
out_of_range	if the peak runs off the edge of the histogram
runtime_error	a Child Algorithm just falls over

Definition at line 266 of file GetEi.cpp.

References advanceProgress(), extractSpec(), findHalfLoc(), FIT_PEAK, GET_COUNT_RATE, getPeakEstimates(), GO_LEFT, GO_RIGHT, HALF_WINDOW, height, m_tempWS, and Mantid::API::WorkspaceHelpers::makeDistribution().

Referenced by exec().

◆ getPeakEstimates()

void Mantid::Algorithms::GetEi::getPeakEstimates	(	double &	height,
		int64_t &	centreInd,
		double &	background
	)		const

private

Finds the largest peak by looping through the histogram and finding the maximum value.

Parameters

height	:: its passed value ignored it is set to the peak height
centreInd	:: passed value is ignored it will be set to the bin index of the peak center
background	:: passed value ignored set mean number of counts per bin in the spectrum

Exceptions

invalid_argument if the peak is not clearly above the background

Definition at line 348 of file GetEi.cpp.

References Mantid::Kernel::Logger::debug(), Mantid::API::Algorithm::g_log, Mantid::API::Algorithm::getPropertyValue(), height, m_tempWS, PEAK_THRESH_H, Mantid::Geometry::X, and Mantid::Geometry::Y.

Referenced by getPeakCentre().

◆ init()

void Mantid::Algorithms::GetEi::init ( )

overrideprivatevirtual

Virtual method - must be overridden by concrete algorithm.

Implements Mantid::API::Algorithm.

Definition at line 49 of file GetEi.cpp.

References Mantid::API::Algorithm::declareProperty(), Mantid::Kernel::Direction::Input, m_fracCompl, and Mantid::Kernel::Direction::Output.

◆ name()

const std::string Mantid::Algorithms::GetEi::name ( ) const

inlineoverridevirtual

Algorithm's name for identification overriding a virtual method.

Implements Mantid::API::Algorithm.

Definition at line 42 of file GetEi.h.

◆ neutron_E_At()

double Mantid::Algorithms::GetEi::neutron_E_At ( double speed ) const

private

Get the kinetic energy of a neuton in joules given it speed using E=mv^2/2.

Parameters

speed :: the instantanious speed of a neutron in metres per second

Returns: the energy in joules

Definition at line 457 of file GetEi.cpp.

References Mantid::PhysicalConstants::NeutronMass.

Referenced by exec().

◆ summary()

const std::string Mantid::Algorithms::GetEi::summary ( ) const

inlineoverridevirtual

Summary of algorithms purpose.

Implements Mantid::API::Algorithm.

Definition at line 44 of file GetEi.h.

◆ timeToFly()

double Mantid::Algorithms::GetEi::timeToFly	(	double	s,
		double	E_KE
	)		const

private

Uses E_KE = mv^2/2 and s = vt to calculate the time required for a neutron to travel a distance, s.

Parameters

s	:: ditance travelled in meters
E_KE	:: kinetic energy in meV

Returns: the time to taken to travel that uninterrupted distance in seconds

Definition at line 240 of file GetEi.cpp.

References Mantid::PhysicalConstants::meV, and Mantid::PhysicalConstants::NeutronMass.

Referenced by exec().

◆ version()

int Mantid::Algorithms::GetEi::version ( ) const

inlineoverridevirtual

Algorithm's version for identification overriding a virtual method.

Implements Mantid::API::Algorithm.

Definition at line 50 of file GetEi.h.

Member Data Documentation

◆ CROP

const double Mantid::Algorithms::GetEi::CROP = 0.15

staticprivate

fraction of algorithm time taken up with running CropWorkspace

Definition at line 97 of file GetEi.h.

Referenced by extractSpec().

◆ FIT_PEAK

const double Mantid::Algorithms::GetEi::FIT_PEAK = 0.2

staticprivate

single call to ConvertToDistribution

fraction required to find a peak

Definition at line 100 of file GetEi.h.

Referenced by getPeakCentre().

◆ GET_COUNT_RATE

const double Mantid::Algorithms::GetEi::GET_COUNT_RATE = 0.15

staticprivate

fraction of algorithm taken by a

Definition at line 98 of file GetEi.h.

Referenced by getPeakCentre().

◆ HALF_WINDOW

const double Mantid::Algorithms::GetEi::HALF_WINDOW = 8.0 / 100

staticprivate

the range of TOF X-values over which the peak will be searched is double this value, i.e.

from the estimate of the peak position the search will go forward by this fraction and back by this fraction

Definition at line 86 of file GetEi.h.

Referenced by exec(), findHalfLoc(), and getPeakCentre().

◆ m_fracCompl

double Mantid::Algorithms::GetEi::m_fracCompl

private

An estimate of the percentage of the algorithm runtimes that has been completed.

Definition at line 59 of file GetEi.h.

Referenced by advanceProgress(), extractSpec(), and init().

◆ m_tempWS

API::MatrixWorkspace_sptr Mantid::Algorithms::GetEi::m_tempWS

private

name of the tempory workspace that we create and use

Definition at line 56 of file GetEi.h.

Referenced by extractSpec(), findHalfLoc(), getPeakCentre(), and getPeakEstimates().

◆ PEAK_THRESH_A

const double Mantid::Algorithms::GetEi::PEAK_THRESH_A = 5.0

staticprivate

ignore peaks where the half width times the ratio of the peak height to the background is less this

Definition at line 91 of file GetEi.h.

Referenced by findHalfLoc().

◆ PEAK_THRESH_H

const double Mantid::Algorithms::GetEi::PEAK_THRESH_H = 3.0

staticprivate

ignore an peaks that are less than this factor of the background

Definition at line 88 of file GetEi.h.

Referenced by getPeakEstimates().

◆ PEAK_THRESH_W

const int64_t Mantid::Algorithms::GetEi::PEAK_THRESH_W = 3

staticprivate

for peaks where the distance to the half heigth is less than this number of bins in either direction e.g.

the FWHM is less than twice this number

Definition at line 94 of file GetEi.h.

Referenced by findHalfLoc().

The documentation for this class was generated from the following files:

Framework/Algorithms/inc/MantidAlgorithms/GetEi.h
Framework/Algorithms/src/GetEi.cpp

Public Member Functions

Private Types

Private Member Functions

Private Attributes

Static Private Attributes

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ direction

Constructor & Destructor Documentation

◆ GetEi()

Member Function Documentation

◆ advanceProgress()

◆ category()

◆ exec()

◆ extractSpec()

◆ findHalfLoc()

◆ getGeometry()

◆ getMonitorWsIndexs()

◆ getPeakCentre()

◆ getPeakEstimates()

◆ init()

◆ name()

◆ neutron_E_At()

◆ summary()

◆ timeToFly()

◆ version()

Member Data Documentation

◆ CROP

◆ FIT_PEAK

◆ GET_COUNT_RATE

◆ HALF_WINDOW

◆ m_fracCompl

◆ m_tempWS

◆ PEAK_THRESH_A

◆ PEAK_THRESH_H

◆ PEAK_THRESH_W