OEFPDatabaseOptions¶

class OEFPDatabaseOptions

The OEFPDatabaseOptions class allows setting options on a per-search basis. This class is used to control the behavior of:

the following methods of the OEFPDatabase class
- OEFPDatabase.GetScores
- OEFPDatabase.GetSortedScores
the following methods of the OEFastFPDatabase class

See also

Example code in Similarity calculation with an option class section
Example code in Sorted similarity calculation with an option class section
Example code in Searching fast fingerprint database section

The OEFPDatabaseOptions class stores the following properties:

Property	Get method	Set method	Corresponding namespace / type
cutoff value	`GetCutoff`	`SetCutoff` / `HasCutoff`	floating point number
order of sorting	`GetDescendingOrder`	`SetDescendingOrder`	boolean
max number of scores	`GetLimit`	`SetLimit`	integer `0` means no limit
similarity method	`GetSimFunc`	`SetSimFunc`	`OESimMeasure`
\(\alpha\) and \(\beta\) for `Tversky`	`GetTverskyAlpha` / `GetTverskyBeta`	`SetTverskyCoeffs`	floating point number
numper of processors	`GetNumProcessors`	`SetNumProcessors`	integer `0` means `OEGetNumProcessors`

Constructors¶

OEFPDatabaseOptions()

Default constructor.

**Default parameters of OEFPDatabaseOptions**¶
Property	Default value
cutoff value	no cutoff set
order of sorting	true (means descending order)
max number of scores	0 (means no limit)
similarity method	`OESimMeasure_Tanimoto`
\(\alpha\) and \(\beta\) for `Tversky`	\(\alpha = 0.95, \beta = 0.05\)
number of processors	1

OEFPDatabaseOptions(const unsigned limit,
                    const unsigned simfunc=OESimMeasure::Tanimoto)

Constructs an OEFPDatabaseOptions object with a limit on the number of similarity scores returned and a similarity method from the OESimMeasure namespace. The returned scores will be in descending order and applying no cutoff value.

OEFPDatabaseOptions(const OEFPDatabaseOptions &rhs)

Copy constructors.

operator=¶

OEFPDatabaseOptions &operator=(const OEFPDatabaseOptions &rhs)

Assignment operator.

ClearCutoff¶

void ClearCutoff()

Removes the cutoff value previously set by the OEFPDatabaseOptions.SetCutoff method. After clearing the cutoff value, OEFPDatabaseOptions.HasCutoff method will return false.

See also

OEFPDatabaseOptions.HasCutoff method
OEFPDatabaseOptions.GetCutoff method
OEFPDatabaseOptions.SetCutoff method

GetCutoff¶

float GetCutoff() const

Returns the cutoff value previously set by the OEFPDatabase.SetCutoff method.

See also

OEFPDatabaseOptions.ClearCutoff method
OEFPDatabaseOptions.HasCutoff method
OEFPDatabaseOptions.SetCutoff method

GetDescendingOrder¶

bool GetDescendingOrder() const

Returns whether the similarity scores will be returned in descending or in ascending order.

See also

OEFPDatabaseOptions.SetDescendingOrder method

GetLimit¶

unsigned GetLimit() const

Returns the maximum number of similarity scores returned.

See also

OEFPDatabaseOptions.SetLimit method

GetSimFunc¶

unsigned GetSimFunc() const

Returns the similarity measure used to evaluate fingerprint similarities. The return value is taken from the OESimMeasure namespace.

See also

OEFPDatabaseOptions.SetSimFunc method

GetNumProcessors¶

unsigned GetNumProcessors()

Returns the number of threads that are used to search fingerprints when calling the OEFastFPDatabase.SortedSearch method.

See also

OEFPDatabaseOptions.SetNumProcessors method

GetTverskyAlpha¶

float GetTverskyAlpha() const

Returns the \(\alpha\) parameter of the Tversky similarity.

See also

OEFPDatabaseOptions.SetTverskyCoeffs method
OETverskySim class

GetTverskyBeta¶

float GetTverskyBeta() const

Returns the \(\beta\) parameter of the Tversky similarity.

See also

OEFPDatabaseOptions.SetTverskyCoeffs method
OETverskySim class

HasCutoff¶

bool HasCutoff() const

Returns whether the cutoff value of the OEFPDatabaseOptions object has been set by the OEFPDatabaseOptions.SetCutoff method.

See also

OEFPDatabaseOptions.ClearCutoff method
OEFPDatabaseOptions.GetCutoff method
OEFPDatabaseOptions.SetCutoff method

SetCutoff¶

void SetCutoff(const float cutoff)

Sets the cutoff value of the OEFPDatabaseOptions object.

See also

OEFPDatabaseOptions.ClearCutoff method
OEFPDatabaseOptions.GetCutoff method
OEFPDatabaseOptions.HasCutoff method

SetDescendingOrder¶

void SetDescendingOrder(const bool descending=true)

Sets whether the similarity scores will be returned in descending or in ascending order.

Note

This method has no effect on the OEFPDatabase.GetScores method.

See also

OEFPDatabaseOptions.GetDescendingOrder method

SetLimit¶

void SetLimit(const unsigned limit)

Sets the maximum number of similarity scores returned.

limit: If it is set to zero, then all similarity scores are returned.

Note

This method has no effect on the OEFPDatabase.GetScores method.

See also

OEFPDatabaseOptions.GetLimit method

SetSimFunc¶

void SetSimFunc(const unsigned simtype)

Sets the similarity measure used to evaluate fingerprint similarities.

simtype: This value has to be from the OESimMeasure namespace.

See also

OEFPDatabaseOptions.GetSimFunc method

SetNumProcessors¶

void SetNumProcessors(const unsigned nrps)

Sets the number of threads that are used to search fingerprints when calling the OEFastFPDatabase.SortedSearch method. When set to 0, the number of processors used will be the number returned by the OEGetNumProcessors function.

Multi-threaded fingerprint search is currently only available in OEFastFPDatabaseMemoryType_MemoryMapped and OEFastFPDatabaseMemoryType_InMemory modes.

SetTverskyCoeffs¶

void SetTverskyCoeffs(const float alpha=0.95f, const float beta=0.05f)

Sets \(\alpha\) and \(\beta\) parameters for the Tversky similarity.

See also

OEFPDatabaseOptions.GetTverskyAlpha method
OEFPDatabaseOptions.GetTverskyBeta method
OETverskySim class