Package weka.core
Class BinarySparseInstance
- java.lang.Object
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- weka.core.Instance
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- weka.core.SparseInstance
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- weka.core.BinarySparseInstance
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- All Implemented Interfaces:
java.io.Serializable
,Copyable
,RevisionHandler
public class BinarySparseInstance extends SparseInstance
Class for storing a binary-data-only instance as a sparse vector. A sparse instance only requires storage for those attribute values that are non-zero. Since the objective is to reduce storage requirements for datasets with large numbers of default values, this also includes nominal attributes -- the first nominal value (i.e. that which has index 0) will not require explicit storage, so rearrange your nominal attribute value orderings if necessary. Missing values are not supported, and will be treated as 1 (true).- Version:
- $Revision: 1.13 $
- See Also:
- Serialized Form
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Constructor Summary
Constructors Constructor Description BinarySparseInstance(double weight, double[] attValues)
Constructor that generates a sparse instance from the given parameters.BinarySparseInstance(double weight, int[] indices, int maxNumValues)
Constructor that inititalizes instance variable with given values.BinarySparseInstance(int numAttributes)
Constructor of an instance that sets weight to one, all values to 1, and the reference to the dataset to null.BinarySparseInstance(Instance instance)
Constructor that generates a sparse instance from the given instance.BinarySparseInstance(SparseInstance instance)
Constructor that copies the info from the given instance.
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Method Summary
All Methods Static Methods Instance Methods Concrete Methods Modifier and Type Method Description java.lang.Object
copy()
Produces a shallow copy of this instance.java.lang.String
getRevision()
Returns the revision string.static void
main(java.lang.String[] options)
Main method for testing this class.Instance
mergeInstance(Instance inst)
Merges this instance with the given instance and returns the result.void
replaceMissingValues(double[] array)
Does nothing, since we don't support missing values.void
setValue(int attIndex, double value)
Sets a specific value in the instance to the given value (internal floating-point format).void
setValueSparse(int indexOfIndex, double value)
Sets a specific value in the instance to the given value (internal floating-point format).double[]
toDoubleArray()
Returns the values of each attribute as an array of doubles.java.lang.String
toString()
Returns the description of one instance in sparse format.double
value(int attIndex)
Returns an instance's attribute value in internal format.double
valueSparse(int indexOfIndex)
Returns an instance's attribute value in internal format.-
Methods inherited from class weka.core.SparseInstance
attributeSparse, index, isMissing, locateIndex, numAttributes, numValues
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Methods inherited from class weka.core.Instance
attribute, classAttribute, classIndex, classIsMissing, classValue, dataset, deleteAttributeAt, enumerateAttributes, equalHeaders, hasMissingValue, insertAttributeAt, isMissing, isMissingSparse, isMissingValue, missingValue, numClasses, relationalValue, relationalValue, setClassMissing, setClassValue, setClassValue, setDataset, setMissing, setMissing, setValue, setValue, setValue, setWeight, stringValue, stringValue, toString, toString, value, weight
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Constructor Detail
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BinarySparseInstance
public BinarySparseInstance(Instance instance)
Constructor that generates a sparse instance from the given instance. Reference to the dataset is set to null. (ie. the instance doesn't have access to information about the attribute types)- Parameters:
instance
- the instance from which the attribute values and the weight are to be copied
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BinarySparseInstance
public BinarySparseInstance(SparseInstance instance)
Constructor that copies the info from the given instance. Reference to the dataset is set to null. (ie. the instance doesn't have access to information about the attribute types)- Parameters:
instance
- the instance from which the attribute info is to be copied
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BinarySparseInstance
public BinarySparseInstance(double weight, double[] attValues)
Constructor that generates a sparse instance from the given parameters. Reference to the dataset is set to null. (ie. the instance doesn't have access to information about the attribute types)- Parameters:
weight
- the instance's weightattValues
- a vector of attribute values
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BinarySparseInstance
public BinarySparseInstance(double weight, int[] indices, int maxNumValues)
Constructor that inititalizes instance variable with given values. Reference to the dataset is set to null. (ie. the instance doesn't have access to information about the attribute types)- Parameters:
weight
- the instance's weightindices
- the indices of the given values in the full vectormaxNumValues
- the maximium number of values that can be stored
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BinarySparseInstance
public BinarySparseInstance(int numAttributes)
Constructor of an instance that sets weight to one, all values to 1, and the reference to the dataset to null. (ie. the instance doesn't have access to information about the attribute types)- Parameters:
numAttributes
- the size of the instance
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Method Detail
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copy
public java.lang.Object copy()
Produces a shallow copy of this instance. The copy doesn't have access to a dataset.- Specified by:
copy
in interfaceCopyable
- Overrides:
copy
in classSparseInstance
- Returns:
- the shallow copy
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mergeInstance
public Instance mergeInstance(Instance inst)
Merges this instance with the given instance and returns the result. Dataset is set to null.- Overrides:
mergeInstance
in classSparseInstance
- Parameters:
inst
- the instance to be merged with this one- Returns:
- the merged instances
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replaceMissingValues
public void replaceMissingValues(double[] array)
Does nothing, since we don't support missing values.- Overrides:
replaceMissingValues
in classSparseInstance
- Parameters:
array
- containing the means and modes
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setValue
public void setValue(int attIndex, double value)
Sets a specific value in the instance to the given value (internal floating-point format). Performs a deep copy of the vector of attribute values before the value is set.- Overrides:
setValue
in classSparseInstance
- Parameters:
attIndex
- the attribute's indexvalue
- the new attribute value (If the corresponding attribute is nominal (or a string) then this is the new value's index as a double).
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setValueSparse
public void setValueSparse(int indexOfIndex, double value)
Sets a specific value in the instance to the given value (internal floating-point format). Performs a deep copy of the vector of attribute values before the value is set.- Overrides:
setValueSparse
in classSparseInstance
- Parameters:
indexOfIndex
- the index of the attribute's indexvalue
- the new attribute value (If the corresponding attribute is nominal (or a string) then this is the new value's index as a double).
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toDoubleArray
public double[] toDoubleArray()
Returns the values of each attribute as an array of doubles.- Overrides:
toDoubleArray
in classSparseInstance
- Returns:
- an array containing all the instance attribute values
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toString
public java.lang.String toString()
Returns the description of one instance in sparse format. If the instance doesn't have access to a dataset, it returns the internal floating-point values. Quotes string values that contain whitespace characters.- Overrides:
toString
in classSparseInstance
- Returns:
- the instance's description as a string
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value
public double value(int attIndex)
Returns an instance's attribute value in internal format.- Overrides:
value
in classSparseInstance
- Parameters:
attIndex
- the attribute's index- Returns:
- the specified value as a double (If the corresponding attribute is nominal (or a string) then it returns the value's index as a double).
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valueSparse
public final double valueSparse(int indexOfIndex)
Returns an instance's attribute value in internal format. Does exactly the same thing as value() if applied to an Instance.- Overrides:
valueSparse
in classInstance
- Parameters:
indexOfIndex
- the index of the attribute's index- Returns:
- the specified value as a double (If the corresponding attribute is nominal (or a string) then it returns the value's index as a double).
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main
public static void main(java.lang.String[] options)
Main method for testing this class.- Parameters:
options
- the command line options - ignored
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getRevision
public java.lang.String getRevision()
Returns the revision string.- Specified by:
getRevision
in interfaceRevisionHandler
- Overrides:
getRevision
in classSparseInstance
- Returns:
- the revision
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