Dataset Expression evaluates a controlled arithmetic expression over
bound symbols. It uses the shared Scientific Analysis parser, Unit
Registry dimensional checks, and the public NUMERIC_API_v1
operation catalog. The Operations button lists expression functions
directly from catalog metadata, including argument, shape, unit and
nonfinite behavior. It can insert a function name into the Expression
field. Arbitrary Octave source is not accepted.
Each binding has a unique symbol and one source kind:
| Kind | Required fields | Meaning |
|---|---|---|
series |
Variable | Selected rows of one stable Dataset variable. |
literal |
Scalar, optional Unit | A finite numeric scalar. Blank Unit means dimensionless
(1). |
metadata |
Metadata key, optional Unit | An exact Dataset Metadata key whose value is a finite numeric scalar. |
row |
Variable, one-based Source row | One scalar from the original Dataset row, read through Table Stream. |
selection |
Variable, Selection aggregate | Mean, median, minimum, maximum or sum over the selected rows. An enabled Selection is required. |
Variable bindings persist stable dataset_id and
variable_id in the saved calculation definition. A unitless
source variable requires an explicit Unit; a unit in the Dataset schema
takes precedence. Arithmetic converts linear units to canonical
dimensions and validates an optional requested Output unit. Semantic or
nonlinear units cannot participate in strict arithmetic. Only one source
Dataset is accepted; the module performs no implicit cross-Dataset
alignment.
The result must be a real numeric scalar or a vector with one element
per selected source row. A scalar becomes a one-row published Dataset. A
vector becomes a published Dataset containing source_row
and the named result variable. Dataset Publication records source IDs,
expression, Selection and producer provenance. The source remains
unchanged. The full selected vector is retained in memory.
The module writes expression_definition.ini alongside
the report. It contains the expression and stable symbol bindings. To
reuse it in another run, set Saved definition file to
its absolute path or a path relative to the current Session root; the
current source Dataset must have the same stable ID. The selected result
Dataset ID and variable ID remain controlled by the current run
configuration. The module configuration and binding table also persist
in the Session manifest.