Dimensions

A dimension is an axis of the model, such as snapshot or generator. Declarations are indexed by it, and sum reduces over it. A map from one axis onto another is a relation.

dimensions

dimensions:
  snapshot: { dtype: int }
  generator: { dtype: str }

Every dimension named anywhere in the file is declared here.

Field
dtype	float, int, str, datetime	default str
description	free text	default null

The members of a dimension arrive with the data, in the order the table gives them. shift, sum_back and position() count along that order, and everything indexed by the dimension is matched to its members by label.

Whether to declare a column of data as a dimension, a relation or a parameter is decided in declare a column of data.