COVAR_POP() OVER ...
All functions > WINDOW FUNCTION > COVAR_POP() OVER ...
Returns the population covariance over the window frame.
Syntax
COVAR_POP(expr_y, expr_x) OVER ([PARTITION BY expr [, ...]] [ORDER BY sort_item [, ...]] [ROWS|RANGE|GROUPS frame])
Notes
- Computes population covariance (divides by N) over a window
- NULL values in either expression are excluded
See also
Examples
FeatureQL
SELECT
f1 := ZIP(ARRAY[1,2,3] AS id, ARRAY[1.0E0,2.0E0,3.0E0] AS y, ARRAY[1.0E0,2.0E0,4.0E0] AS x).TRANSFORM(SELECT COVAR_POP(y, x) OVER (ORDER BY id ASC)).UNWRAP() -- Population covariance over the frame
;Result
| f1 ARRAY |
|---|
| [0.00, 0.25, 1.00] |