Create a summation AST node — ast

Constructs an abstract syntax tree (AST) node representing a summation over an index. The index is typically a set, dims or when object if filtering is applied to the index.

Usage

ast_sum(index = ast_dims(), value, domain = NULL)

Arguments

index: An AST node representing the index variable(s) (e.g., ast_dims("t")).
value: An AST node representing the expression to be summed.
domain: An optional AST node representing a domain condition. This can be a mapping, a logical condition (e.g., from a $-filter), or a parameter. Use NULL if there is no restriction.

Value

An object of class ast and sum.