The following general syntax structure can be used for chart expressions, with many optional parameters:
expression ::= ( constant | expressionname | operator1 expression | expression operator2 expression | function | aggregation function | (expression ) )
where:
constant is a string (a text, a date or a time) enclosed by single straight quotation marks, or a number. Constants are written without thousands separator and with a decimal point as decimal separator.
expressionname is the name (label) of another expression in the same chart.
operator1 is a unary operator (working on one expression, the one to the right).
operator2 is a binary operator (working on two expressions, one on each side).
function ::= functionname ( parameters )
parameters ::= expression { , expression }
The number and types of parameters are not arbitrary. They depend on the function used.
aggregationfunction ::= aggregationfunctionname ( parameters2 )
parameters2 ::= aggrexpression { , aggrexpression }
The number and types of parameters are not arbitrary. They depend on the function used.