Package weka.core

Class AbstractInstance

java.lang.Object
weka.core.AbstractInstance
All Implemented Interfaces:
Serializable, Copyable, Instance, RevisionHandler
Direct Known Subclasses:
DenseInstance, SparseInstance
public abstract class AbstractInstance extends Object implements Instance, Serializable, RevisionHandler
Abstract class providing common functionality for the original instance implementations.
Version:
$Revision: 10649 $
Author:
Eibe Frank (eibe@cs.waikato.ac.nz)
See Also:

  • Field Details

    • s_numericAfterDecimalPoint

      public static int s_numericAfterDecimalPoint
      Default max number of digits after the decimal point for numeric values

  • Constructor Details

    • AbstractInstance

      public AbstractInstance()

  • Method Details

    • attribute

      public Attribute attribute(int index)
      Returns the attribute with the given index.
      Specified by:
      attribute in interface Instance
      Parameters:
      index - the attribute's index
      Returns:
      the attribute at the given position
      Throws:
      UnassignedDatasetException - if instance doesn't have access to a dataset

    • attributeSparse

      public Attribute attributeSparse(int indexOfIndex)
      Returns the attribute with the given index in the sparse representation.
      Specified by:
      attributeSparse in interface Instance
      Parameters:
      indexOfIndex - the index of the attribute's index
      Returns:
      the attribute at the given position
      Throws:
      UnassignedDatasetException - if instance doesn't have access to a dataset

    • classAttribute

      public Attribute classAttribute()
      Returns class attribute.
      Specified by:
      classAttribute in interface Instance
      Returns:
      the class attribute
      Throws:
      UnassignedDatasetException - if the class is not set or the instance doesn't have access to a dataset

    • classIndex

      public int classIndex()
      Returns the class attribute's index.
      Specified by:
      classIndex in interface Instance
      Returns:
      the class index as an integer
      Throws:
      UnassignedDatasetException - if instance doesn't have access to a dataset

    • classIsMissing

      public boolean classIsMissing()
      Tests if an instance's class is missing.
      Specified by:
      classIsMissing in interface Instance
      Returns:
      true if the instance's class is missing
      Throws:
      UnassignedClassException - if the class is not set or the instance doesn't have access to a dataset

    • classValue

      public double classValue()
      Returns an instance's class value in internal format. (ie. as a floating-point number)
      Specified by:
      classValue in interface Instance
      Returns:
      the corresponding value as a double (If the corresponding attribute is nominal (or a string) then it returns the value's index as a double).
      Throws:
      UnassignedClassException - if the class is not set or the instance doesn't have access to a dataset

    • dataset

      public Instances dataset()
      Returns the dataset this instance has access to. (ie. obtains information about attribute types from) Null if the instance doesn't have access to a dataset.
      Specified by:
      dataset in interface Instance
      Returns:
      the dataset the instance has accesss to

    • deleteAttributeAt

      public void deleteAttributeAt(int position)
      Deletes an attribute at the given position (0 to numAttributes() - 1). Only succeeds if the instance does not have access to any dataset because otherwise inconsistencies could be introduced.
      Specified by:
      deleteAttributeAt in interface Instance
      Parameters:
      position - the attribute's position
      Throws:
      RuntimeException - if the instance has access to a dataset

    • enumerateAttributes

      public Enumeration<Attribute> enumerateAttributes()
      Returns an enumeration of all the attributes.
      Specified by:
      enumerateAttributes in interface Instance
      Returns:
      enumeration of all the attributes
      Throws:
      UnassignedDatasetException - if the instance doesn't have access to a dataset

    • equalHeaders

      public boolean equalHeaders(Instance inst)
      Tests if the headers of two instances are equivalent.
      Specified by:
      equalHeaders in interface Instance
      Parameters:
      inst - another instance
      Returns:
      true if the header of the given instance is equivalent to this instance's header
      Throws:
      UnassignedDatasetException - if instance doesn't have access to any dataset

    • equalHeadersMsg

      public String equalHeadersMsg(Instance inst)
      Checks if the headers of two instances are equivalent. If not, then returns a message why they differ.
      Specified by:
      equalHeadersMsg in interface Instance
      Parameters:
      dataset - another instance
      Returns:
      null if the header of the given instance is equivalent to this instance's header, otherwise a message with details on why they differ

    • hasMissingValue

      public boolean hasMissingValue()
      Tests whether an instance has a missing value. Skips the class attribute if set.
      Specified by:
      hasMissingValue in interface Instance
      Returns:
      true if instance has a missing value.
      Throws:
      UnassignedDatasetException - if instance doesn't have access to any dataset

    • insertAttributeAt

      public void insertAttributeAt(int position)
      Inserts an attribute at the given position (0 to numAttributes()). Only succeeds if the instance does not have access to any dataset because otherwise inconsistencies could be introduced.
      Specified by:
      insertAttributeAt in interface Instance
      Parameters:
      position - the attribute's position
      Throws:
      RuntimeException - if the instance has accesss to a dataset
      IllegalArgumentException - if the position is out of range

    • isMissing

      public boolean isMissing(int attIndex)
      Tests if a specific value is "missing".
      Specified by:
      isMissing in interface Instance
      Parameters:
      attIndex - the attribute's index
      Returns:
      true if the value is "missing"

    • isMissingSparse

      public boolean isMissingSparse(int indexOfIndex)
      Tests if a specific value is "missing", given an index in the sparse representation.
      Specified by:
      isMissingSparse in interface Instance
      Parameters:
      indexOfIndex - the index of the attribute's index
      Returns:
      true if the value is "missing"

    • isMissing

      public boolean isMissing(Attribute att)
      Tests if a specific value is "missing". The given attribute has to belong to a dataset.
      Specified by:
      isMissing in interface Instance
      Parameters:
      att - the attribute
      Returns:
      true if the value is "missing"

    • numClasses

      public int numClasses()
      Returns the number of class labels.
      Specified by:
      numClasses in interface Instance
      Returns:
      the number of class labels as an integer if the class attribute is nominal, 1 otherwise.
      Throws:
      UnassignedDatasetException - if instance doesn't have access to any dataset

    • setClassMissing

      public void setClassMissing()
      Sets the class value of an instance to be "missing". A deep copy of the vector of attribute values is performed before the value is set to be missing.
      Specified by:
      setClassMissing in interface Instance
      Throws:
      UnassignedClassException - if the class is not set
      UnassignedDatasetException - if the instance doesn't have access to a dataset

    • setClassValue

      public void setClassValue(double value)
      Sets the class value of an instance to the given value (internal floating-point format). A deep copy of the vector of attribute values is performed before the value is set.
      Specified by:
      setClassValue in interface Instance
      Parameters:
      value - the new attribute value (If the corresponding attribute is nominal (or a string) then this is the new value's index as a double).
      Throws:
      UnassignedClassException - if the class is not set
      UnaddignedDatasetException - if the instance doesn't have access to a dataset

    • setClassValue

      public final void setClassValue(String value)
      Sets the class value of an instance to the given value. A deep copy of the vector of attribute values is performed before the value is set.
      Specified by:
      setClassValue in interface Instance
      Parameters:
      value - the new class value (If the class is a string attribute and the value can't be found, the value is added to the attribute).
      Throws:
      UnassignedClassException - if the class is not set
      UnassignedDatasetException - if the dataset is not set
      IllegalArgumentException - if the attribute is not nominal or a string, or the value couldn't be found for a nominal attribute

    • setDataset

      public final void setDataset(Instances instances)
      Sets the reference to the dataset. Does not check if the instance is compatible with the dataset. Note: the dataset does not know about this instance. If the structure of the dataset's header gets changed, this instance will not be adjusted automatically.
      Specified by:
      setDataset in interface Instance
      Parameters:
      instances - the reference to the dataset

    • setMissing

      public final void setMissing(int attIndex)
      Sets a specific value to be "missing". Performs a deep copy of the vector of attribute values before the value is set to be missing.
      Specified by:
      setMissing in interface Instance
      Parameters:
      attIndex - the attribute's index

    • setMissing

      public final void setMissing(Attribute att)
      Sets a specific value to be "missing". Performs a deep copy of the vector of attribute values before the value is set to be missing. The given attribute has to belong to a dataset.
      Specified by:
      setMissing in interface Instance
      Parameters:
      att - the attribute

    • setValue

      public final void setValue(int attIndex, String value)
      Sets a value of a nominal or string attribute to the given value. Performs a deep copy of the vector of attribute values before the value is set.
      Specified by:
      setValue in interface Instance
      Parameters:
      attIndex - the attribute's index
      value - the new attribute value (If the attribute is a string attribute and the value can't be found, the value is added to the attribute).
      Throws:
      UnassignedDatasetException - if the dataset is not set
      IllegalArgumentException - if the selected attribute is not nominal or a string, or the supplied value couldn't be found for a nominal attribute

    • setValue

      public final void setValue(Attribute att, 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, so if you are planning on calling setValue many times it may be faster to create a new instance using toDoubleArray. The given attribute has to belong to a dataset.
      Specified by:
      setValue in interface Instance
      Parameters:
      att - the attribute
      value - the new attribute value (If the corresponding attribute is nominal (or a string) then this is the new value's index as a double).

    • setValue

      public final void setValue(Attribute att, String value)
      Sets a value of an nominal or string attribute to the given value. Performs a deep copy of the vector of attribute values before the value is set, so if you are planning on calling setValue many times it may be faster to create a new instance using toDoubleArray. The given attribute has to belong to a dataset.
      Specified by:
      setValue in interface Instance
      Parameters:
      att - the attribute
      value - the new attribute value (If the attribute is a string attribute and the value can't be found, the value is added to the attribute).
      Throws:
      IllegalArgumentException - if the the attribute is not nominal or a string, or the value couldn't be found for a nominal attribute

    • setWeight

      public final void setWeight(double weight)
      Sets the weight of an instance.
      Specified by:
      setWeight in interface Instance
      Parameters:
      weight - the weight

    • relationalValue

      public final Instances relationalValue(int attIndex)
      Returns the relational value of a relational attribute.
      Specified by:
      relationalValue in interface Instance
      Parameters:
      attIndex - the attribute's index
      Returns:
      the corresponding relation as an Instances object
      Throws:
      IllegalArgumentException - if the attribute is not a relation-valued attribute
      UnassignedDatasetException - if the instance doesn't belong to a dataset.

    • relationalValue

      public final Instances relationalValue(Attribute att)
      Returns the relational value of a relational attribute.
      Specified by:
      relationalValue in interface Instance
      Parameters:
      att - the attribute
      Returns:
      the corresponding relation as an Instances object, null if missing
      Throws:
      IllegalArgumentException - if the attribute is not a relation-valued attribute
      UnassignedDatasetException - if the instance doesn't belong to a dataset.

    • stringValue

      public final String stringValue(int attIndex)
      Returns the value of a nominal, string, date, or relational attribute for the instance as a string.
      Specified by:
      stringValue in interface Instance
      Parameters:
      attIndex - the attribute's index
      Returns:
      the value as a string
      Throws:
      IllegalArgumentException - if the attribute is not a nominal, string, date, or relation-valued attribute.
      UnassignedDatasetException - if the instance doesn't belong to a dataset.

    • stringValue

      public final String stringValue(Attribute att)
      Returns the value of a nominal, string, date, or relational attribute for the instance as a string.
      Specified by:
      stringValue in interface Instance
      Parameters:
      att - the attribute
      Returns:
      the value as a string
      Throws:
      IllegalArgumentException - if the attribute is not a nominal, string, date, or relation-valued attribute.
      UnassignedDatasetException - if the instance doesn't belong to a dataset.

    • toStringMaxDecimalDigits

      public final String toStringMaxDecimalDigits(int afterDecimalPoint)
      Returns the description of one instance with any numeric values printed at the supplied maximum number of decimal places. If the instance doesn't have access to a dataset, it returns the internal floating-point values. Quotes string values that contain whitespace characters.
      Specified by:
      toStringMaxDecimalDigits in interface Instance
      Parameters:
      afterDecimalPoint - the maximum number of digits permitted after the decimal point for a numeric value
      Returns:
      the instance's description as a string

    • toString

      public String toString()
      Returns the description of one instance. 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 class Object
      Returns:
      the instance's description as a string

    • toString

      public final String toString(int attIndex)
      Returns the description of one value of the instance as a string. If the instance doesn't have access to a dataset, it returns the internal floating-point value. Quotes string values that contain whitespace characters, or if they are a question mark.
      Specified by:
      toString in interface Instance
      Parameters:
      attIndex - the attribute's index
      Returns:
      the value's description as a string

    • toString

      public final String toString(int attIndex, int afterDecimalPoint)
      Returns the description of one value of the instance as a string. If the instance doesn't have access to a dataset, it returns the internal floating-point value. Quotes string values that contain whitespace characters, or if they are a question mark.
      Specified by:
      toString in interface Instance
      Parameters:
      attIndex - the attribute's index
      afterDecimalPoint - the maximum number of digits permitted after the decimal point for numeric values
      Returns:
      the value's description as a string

    • toString

      public final String toString(Attribute att)
      Returns the description of one value of the instance as a string. If the instance doesn't have access to a dataset it returns the internal floating-point value. Quotes string values that contain whitespace characters, or if they are a question mark. The given attribute has to belong to a dataset.
      Specified by:
      toString in interface Instance
      Parameters:
      att - the attribute
      Returns:
      the value's description as a string

    • toString

      public final String toString(Attribute att, int afterDecimalPoint)
      Returns the description of one value of the instance as a string. If the instance doesn't have access to a dataset it returns the internal floating-point value. Quotes string values that contain whitespace characters, or if they are a question mark. The given attribute has to belong to a dataset.
      Specified by:
      toString in interface Instance
      Parameters:
      att - the attribute
      afterDecimalPoint - the maximum number of decimal places to print
      Returns:
      the value's description as a string

    • value

      public double value(Attribute att)
      Returns an instance's attribute value in internal format. The given attribute has to belong to a dataset.
      Specified by:
      value in interface Instance
      Parameters:
      att - the attribute
      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).

    • valueSparse

      public double valueSparse(int indexOfIndex)
      Returns an instance's attribute value in internal format, given an index in the sparse representation.
      Specified by:
      valueSparse in interface Instance
      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).

    • weight

      public final double weight()
      Returns the instance's weight.
      Specified by:
      weight in interface Instance
      Returns:
      the instance's weight as a double

    • getRevision

      public String getRevision()
      Returns the revision string.
      Specified by:
      getRevision in interface RevisionHandler
      Returns:
      the revision