# SpecifiedStatistics

An operator which computes certain statistical values for the TheInputConcept. The computed values appear in a `ColumnSet` which contains exactly one row with the statistical values, and which belongs to TheOutputConcept.

The sum of all values in an attribute can be computed by specifying a `BaseAttribute` with the parameter AttributesComputeSum. There can be more such attributes; the sum is computed for each. TheOutputConcept must contain a `BaseAttribute` for each sum which is computed; their names must be those of the input attributes, followed by the suffix `"_SUM`".

The total number of entries in an attribute can be computed by specifying a `BaseAttribute` with the parameter AttributesComputeCount. There can be more such attributes; the number of entries is computed for each. TheOutputConcept must contain a `BaseAttribute` for each count which is computed; their names must be those of the input attributes, followed by the suffix "`_COUNT`".

The number of unique values in an attribute can be computed by specifying a `BaseAttribute` with the parameter AttributesComputeUnique. There can be more such attributes; the number of unique values is computed for each. TheOutputConcept must contain a `BaseAttribute` for each number of unique values which is computed; their names must be those of the input attributes, followed by the suffix "`_UNIQUE`".

Further, for a `BaseAttribute` specified with AttributesComputeDistrib, the distribution of its values is computed. For example, if a `BaseAttribute` contains the values 2, 4 and 6, three output `BaseAttribute`s will contain the number of entries in the input where the value was 2, 4 and 6, respectively. For each `BaseAttribute` whose value distribution is to be computed, the possible values must be given with the parameter DistribValues. One entry in this parameter is a comma-separated string containing the different values; in the example, the string would be "`2,4,6`". Thus, the number of entries in AttributesComputeDistrib and DistribValues must be equal. TheOutputConcept must contain the corresponding number of `BaseAttributes` (three in the example); their names must be those of the input attributes, followed by the suffix `"_<value>`". In the example, TheOutputConcept would contain the `BaseAttribute`s "`inputBaName_2`", " `inputBaName_4`" and "`inputBaName_6`".

ParameterName | ObjectType | Type | Remarks
TheInputConcept | CON | IN | inherited
AttributesComputeSum | BA List | IN | numeric
AttributesComputeCount | BA List | IN | (see
AttributesComputeUnique | BA List | IN |
AttributesComputeDistrib | BA List | IN | text)
DistribValues | V List | IN |
TheOutputConcept | CON | OUT | inherited