equals (==)

syntax

• eq(a, b)
• a == b

definition

eq(a, b) or a == b results in a boolean data item indicating if the values of data item a are equal to the values of data item b.

description

The comparison between two missing values (null == null) results in the value false.

applies to

Data items with value types:

• groups: Numeric, Point
• string
• bool

conditions

Data items a and b need to match with regard to their:

• value type
• metric
• domain unit (constants or parameters can be used in comparisons with data items of each domain unit)

since version

5.15

example

1. attribute<bool> AisB (CDomain): expr = "eq(A, B)";    
2. attribute<bool> AisB (CDomain): expr = "A == B";

A	B		AisB
0	0		True
1	2		False
2.5	2.5		True
-100	100		False
999	-999		False
null	0		False
null	null		False
0	null		False
null	100		False
100	null		False

Table CDomain, nr of rows = 10

see also

• equals or both null