Cumulate

arithmetic-functions cumulate

syntax

• cumulate(a)
• cumulate(a, relation)

definition

• cumulate(a) results in an attribute with the cumulation of the non null values of attribute a.
• cumulate(a, relation) results in an attribute with the cumulation of the non null values of attribute a, grouped by the relation. The domain-unit of the resulting attribute is the values unit of the relation attribute.

description

1. For domain units with index-numbers starting from 0 (default), cumulate(const(1, domainunit, uint32)) - 1 is synonym for id(domain unit). It is advised to use the id function in such a case.
2. There is no id(domainunit, relation) function, use cumulate(const(1, domainunit, uint32), relation) - 1 to calculate index numbers for each entry in the relation domain.

applies to

• Attribute a with Numeric value-type
• Relation attribute with value type of the group CanBeDomainUnit

conditions

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 arguments a and relation must match.

since version

6.061

example

1. attribute<uint32> cumulateNrInh       (City) := cumulate(City/NrInhabitants);
2. attribute<uint32> cumulateNrInhRegion (City) := cumulate(City/NrInhabitants, City/Region_rel);

domain City, nr of rows = 7