AttributeStatistics Class Reference
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Attribute statistics class. More...

Collaboration diagram for AttributeStatistics:

Collaboration graph

List of all members.

Public Member Functions

 ~AttributeStatistics ()
 Destructor.
int64_t GetTotal () const
 Gets the number of objects with a non-NULL Value (BASIC statistic).
int64_t GetNull () const
 Gets the number of objects NULL a Value (BASIC statistics).
int64_t GetDistinct () const
 Gets the number of distinct values (BASIC statistics).
const ValueGetMin () const
 Gets the minimum existing value (BASIC statistics).
const ValueGetMax () const
 Gets the maximum existing value (BASIC statistics).
int32_t GetMaxLengthString () const
 Gets the maximum length.
int32_t GetMinLengthString () const
 Gets the minimum length.
double64_t GetAvgLengthString () const
 Gets the average length.
const ValueGetMode () const
 Gets the mode.
int64_t GetModeCount () const
 Gets the number of objects with a Value equal to the mode.
double64_t GetMean () const
 Gets the mean or average.
double64_t GetVariance () const
 Gets the variance.
double64_t GetMedian () const
 Gets the median.

Friends

class Graph


Detailed Description

Attribute statistics class.

It contains statistic data about an attribute.

Some fields are valid just for numerical attributes and others just for string attributes. Also, some statistics are considered BASIC because computing them do not require to traverse all the different values of the attribute. For each getter method the documentation tells if the statistic is BASIC or not. See the Graph class method getAttributeStatistics or check out the SPARKSEE User Manual for more details on this.

Author:
Sparsity Technologies http://www.sparsity-technologies.com

Member Function Documentation

int64_t AttributeStatistics::GetTotal (  )  const [inline]

Gets the number of objects with a non-NULL Value (BASIC statistic).

Returns:
The number of objects with a non-NULL Value.

int64_t AttributeStatistics::GetNull (  )  const [inline]

Gets the number of objects NULL a Value (BASIC statistics).

Returns:
The number of objects NULL a Value.

int64_t AttributeStatistics::GetDistinct (  )  const [inline]

Gets the number of distinct values (BASIC statistics).

Returns:
The number of distinct values.

const Value& AttributeStatistics::GetMin (  )  const [inline]

Gets the minimum existing value (BASIC statistics).

Returns:
The minimum existing value.

const Value& AttributeStatistics::GetMax (  )  const [inline]

Gets the maximum existing value (BASIC statistics).

Returns:
The maximum existing value.

int32_t AttributeStatistics::GetMaxLengthString (  )  const [inline]

Gets the maximum length.

If the attribute is not an string attribute, it just returns 0.

Returns:
The maximum length.

int32_t AttributeStatistics::GetMinLengthString (  )  const [inline]

Gets the minimum length.

If the attribute is not an string attribute, it just returns 0.

Returns:
The minimum length.

double64_t AttributeStatistics::GetAvgLengthString (  )  const [inline]

Gets the average length.

If the attribute is not an string attribute, it just returns 0.

Returns:
The average length.

const Value& AttributeStatistics::GetMode (  )  const [inline]

Gets the mode.

Mode: Most frequent Value.

Returns:
The mode.

int64_t AttributeStatistics::GetModeCount (  )  const [inline]

Gets the number of objects with a Value equal to the mode.

Returns:
The number of objects with a Value equal to the mode.

double64_t AttributeStatistics::GetMean (  )  const [inline]

Gets the mean or average.

Mean or average: Sum of all Values divided by the number of observations.

It is computed just for numerical attributes.

Returns:
The mean.

double64_t AttributeStatistics::GetVariance (  )  const [inline]

Gets the variance.

It is computed just for numerical attributes.

Returns:
The variance.

double64_t AttributeStatistics::GetMedian (  )  const [inline]

Gets the median.

Median: Middle value that separates the higher half from the lower.

If a < b < c, then the median of the list {a, b, c} is b, and if a < b < c < d, then the median of the list {a, b, c, d} is the mean of b and c, i.e. it is (b + c)/2

It is computed just for numerical attributes.

Returns:
The median.


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

Generated on Fri Feb 7 13:09:48 2014 for Sparksee by  doxygen 1.5.6