sum - ObjectVision/GeoDMS GitHub Wiki

Aggregation functions sum

• sum(a)
• sum(a, relation)
• sum_x(a) or sum_x(a, relation) where x in {(|u)int(8|16|32|64), float64, (i|u|d)point }

• sum(a) results in a parameter with the sum of the non null values of attribute a.
• sum(a, relation) results in an attribute with the sum of the non null values of attribute a, grouped by relation. The domain unit of the resulting attribute is the values unit of the relation.
• sum_x(a) or sum_x(a, relation) results in an attribute with the sum of the non null values of attribute a, optionally grouped by relation with as resulting value type the value type x.

• attribute a with Numeric value type
• relation with value type of the group CanBeDomainUnit

1. The values unit of the resulting data item should match with regard to value type and metric with the values unit of attribute a.
2. The domain unit of argument a and relation must match.

• Without relation: O(n) where n = number of elements in the domain of a. Single pass through data.
• With relation: O(n) where n = number of elements in the domain of a. Aggregates values into groups during a single pass.

parameter<uint32>  sumNrInh                := sum(City/NrInhabitants); result = 2250
parameter<float64> sum_float64NrInh        := sum_float64(City/NrInhabitants); result = 2250 as float64
attribute<uint32>  sumNrInhRegion (Region) := sum(City/NrInhabitants, City/Region_rel);

domain City, nr of rows = 7

domain Region, nr of rows = 5