# Expression Syntax

{field_name} - local field
{fiel_name:function} - built-in field's function
{global:parameter_name} - global paramter
{global:parameter_name}[2] - access global parameter array. The value of an array at index 2
{global:parameter_name}["foo"] - access global parameter json object. The value of key "foo"

+ addition
- subtraction
* multiplication
/ division
% modulus
** pow

== equal
!= not equal
< less than
> greater than
<= less than or equal to
>= greater than or equal to

not
and
or

!       - not
&&      - and
||      - or

round(x; p)      - round "x" with the precision of "p"
ceil(x)         - round up to the integer number
floor(x)        - round down to the integer number
abs(x)          - absolute number
max(a; b,...)    - maximal value
min(a; b,...)    - minimal value
pow(x; p)        - "x" raised to the power of "p" (x^p) 
sqrt(x)         - square root of "x"
strlen(x)       - get length of a text; use with text fields
in_array(v; arr) - true if value "v" in in array "arr"
is_selected(field; v) - true if value "v" is checked (used for multi checkbox field)