Since ArchiCAD 10 the interpreter is nagging, thet there are precision problems, when comparing real type values by "=". You have to substitute by equal expressions.

!*** Compare real type values
tlr=0.001  !---> Prüfung:  NOT(ABS()>0)  NOT(ABS()>tlr)

ABS()>tlr
ABS()>0
NOT(ABS()>0)

ABS( A - B )>tlr   ! A<>B
ABS( A - B )<tlr   ! A=B
A - B < tlr        ! A<=B
A - B <-tlr        ! A<B
B - A > tlr        ! A<B
B - A < tlr        ! A>=B
B - A <-tlr        ! A>B
A - B > tlr        ! A>B