Matrix covariance

Matrix functions matr(ix)_(co)var(iance)

syntax

• matr_var(point_att, result_domain)

definition

The matr_var(point_att, result_domain) function calculates the covariance matrix of the point_att, with as resulting domain: result_domain.

The value type of the resulting attribute is the same as the value type of the point_att.

applies to

• attribute point_att with float32 or float64 value type

conditions

1. The value type of point_att and of the result attribute need to match.
2. The domain unit of the point_att attribute must be a Point value type of the group CanBeDomainUnit.
3. The result_domain argument must be a unit of with a Point value type of the group CanBeDomainUnit and match with the result of the matrix covariance calculation in terms of number or rows/columns.

since version

7.184

example

attribute<float32> covariance (GridDomain) := matr_var(src, GridDomain);

src

1	2
3	4

GridDomain, nr of rows = 2, nr of cols = 2

covariance

10	14
14	200

GridDomain, nr of rows = 2, nr of cols = 2