Language reference
Sgn (sign)
Syntax
Sgn(<number>)
π Sgn(change) → direction (Prices)Description
Sgn reports the sign of a number: −1 for negatives, 0 for zero, and 1 for positives. Use it to classify values by direction — up/down/flat, gain/loss — in a single tidy number.
Technical Description
Sgn(x: NUMBER) → NUMBER. Returns the signum of x (−1, 0, or 1). NULL input returns NULL. PURE, DETERMINISTIC, IDEMPOTENT.
Examples
Direction of a price change:
π Sgn(close - open) → direction (Prices)PROJECT Sgn(close - open) -> direction (Prices)Count gainers vs losers:
γ Sgn(change) → dir, COUNT(id) → n (Stocks)GROUP Sgn(change) -> dir, COUNT(id) -> n (Stocks)Pushdown
SQL: folds to SIGN(<e>) on all dialects.
Limitations
NUMBER only; NULL in → NULL out.