FILTER

Returns a subset of an array by keeping only the elements that match a given condition. FILTER is one of the most powerful tools in FormulaScript — used to clean datasets, extract matching values, or prepare smaller result sets for further analysis.

Syntax

FILTER(array, condition)

• array (Array): The source array to filter.

• condition (Boolean | Function | Array):

  • A function: evaluated for each element (function(item) -> boolean).

  • A boolean expression: tested directly against each element.

  • An array: treated as a list of allowed values.

Returns: Array – A new array containing only the elements that satisfy the condition.

Aliases: WHERE, SELECT, FILTERARRAY

Examples

Simple Example

FILTER(ARRAY(1,2,3,4,5), function(x: x > 3))     // [4, 5]
FILTER(ARRAY("A","B","C"), ARRAY("B","C"))       // ["B","C"]
FILTER(ARRAY(true,false,true), true)              // [true, true]

Business Example: Filter High-Value Orders

Filter order totals over $500 for a sales report:

FILTER(ORDER_TOTALS, function(TOTAL: TOTAL > 500))

Returns only high-value transactions for executive dashboards or commission calculations.

Business Example: Extract Active Projects

Keep only active projects visible on dashboards using allowed-value filtering:

FILTER(PROJECT_STATUS_LIST, ARRAY("Active", "In Progress"))

Business Example: Filter Table Rows

Extract rows from a data table where the first column (total) exceeds 1000:

FILTER(SALES_TABLE, function(row: row[0] > 1000))

Piping for Readability

Chain filters with other array functions using pipe syntax:

ORDER_TOTALS | FILTER(x: x > 500) | SUM

PRICES | MAP(p: p * 1.21) | FILTER(p: p < 100) | COUNT

Common Mistakes

• When using a function, use function(x: ...) syntax or shorthand x: ... in pipes.

• Returns an empty array ([]) if no matches are found — not null.

• For table data, access columns by index: row[0], row[1], etc.

• Nested filtering is supported: FILTER(FILTER(data, x: x > 10), x: x < 100)

See Also

MAP · TABLEFILTER · ALL · ARRAY