The cluster is a group of observations with the common covariance matrix. The covariance matrix allows to express any combination of correlations among observations in cluster (including uncorrelated observations, where covariance matrix is diagonal). For explanation see Observation data and points.
In the database observations are stored in three tables:
Cluster's covariance matrix is stored in table
Every observation, vector or coordinate in database has to be in some cluster.
conf_idis id of configuration which cluster belongs to.
cclusteridentifies a cluster within one configuration.
bandspecify dimension and bandwidth of covariance matrix. The bandwidth of the diagonal matrix is equal to 0 and a fully-populated covariance matrix has a bandwidth of
bandmaximum possible value is
tagspecifies type of observations in cluster which also implies the table where they are stored in.
Observations, vectors and coordinates are identified by
configuration id (
conf_id), cluster id
and theirs index (
Observation index (
indx) has to be unique within observations
of one cluster (which belongs to one configuration).
The same applies for vectors and coordinates.
See also Set of observations.
Example (table contents):
conf_id|ccluster|dim|band|tag ----------------------------- 1 |1 |3 |0 |obs 1 |4 |4 |0 |obs