# General syntax for chart expressions

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.

## Learn more

* [Operators](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/Scripting/Operators/operators.htm)