pub fn cov<T>(a: &ChunkedArray<T>, b: &ChunkedArray<T>, ddof: u8) -> Option<f64>where
T: PolarsNumericType,
<T as PolarsNumericType>::Native: AsPrimitive<f64>,
ChunkedArray<T>: ChunkVar,
Expand description
Compute the covariance between two columns.