loader_field

Julia

Julia does not export this type.

TypeScript

interface LoaderField {
    name: string;
    owner: string;
    subkey: string;
    var: string;
    dataSource: DataSource;
    cadence: 'const' | 'discrete';
    unitConversion?: Expression;
    recordsPerSample: 1 | 2;
}

A data-fed PARAMETER lowered to a flattened array input (esm-spec §8.5).

From 1.0.0 a data source is not a component: a model consumes one by declaring a parameter whose update is {kind: "data", source, from: {file_variable}}. The parameter IS the loaded field and owns the units; this descriptor is what lets a simulator execute the source at its cadence and bind the resulting array into the RHS as a read-only input.

Properties

• name — The namespaced parameter symbol, e.g. "Plume.wind".
• owner — The owning component’s namespaced prefix, e.g. "Plume".
• subkey — The data_sources key the parameter’s update names.
• var — The source-file variable the binding names.
• dataSource — The resolved data_sources entry (carries kind / source / temporal).
• cadence — Source-seeded cadence (CONFORMANCE_SPEC §5.7.2): a source WITH a temporal block is time-varying (discrete); one without is read once (const).
• unitConversion — The binding’s declared unit_conversion (§8.5), when the document has one.
• recordsPerSample — The EFFECTIVE records per query time (esm-spec §8.5.1): the binding’s from.records_per_sample, else the source’s temporal.records_per_sample, else 1. With 2 the field holds the record at or before the query time and its successor, stacked along the parameter’s first dimension.

Source

Python

class LoaderField
LoaderField(name: str, owner: str, subkey: str, var: str, data_source: DataSource, cadence: str, unit_conversion: Expr | None = None, records_per_sample: int = 1)

A data-fed PARAMETER lowered to a flattened array input (esm-spec §8.5).

A data source is not a component: there is no loader subsystem and no coupling edge. A model consumes a source by declaring a PARAMETER whose update is {kind: "data", source: <key>, from: {file_variable}} — the parameter IS the loaded field, and it owns the units. Flatten records this descriptor per such parameter so the simulator can execute the source at its cadence and bind the resulting array into the RHS as a read-only input, keyed by the parameter’s namespaced name. A data-fed parameter carries no defining equation: its value is injected, not computed.

cadence follows the source-seeded refinement (CONFORMANCE_SPEC §5.7.2, cadence.py): a source WITH a temporal block is time-varying → "discrete" (refreshed in a discrete solver callback at its cadence); a source WITHOUT temporal is non-time-varying → "const" (read once before integration).

Source

Rust

pub struct LoaderField {
    pub name: String,
    pub owner: String,
    pub source: String,
    pub file_variable: String,
    pub cadence: String,
    pub records_per_sample: u8,
}

One provider-served loaded field the flattened system consumes (esm-spec §8.5; esm-libraries-spec §4.7.5 step 4 loader_fields).

From esm 1.0.0 a data source is not a component: there is no loader subsystem and no coupling edge. A model consumes a source by declaring a PARAMETER whose update is {kind: "data", source: <key>, from: {file_variable}} — the parameter IS the loaded field and owns the units. Flatten records this descriptor per such parameter so a consumer can execute the source at its cadence and bind the resulting array into the RHS as a read-only input, without re-reading the source document.

Source · Rust docs

Go

type LoaderField struct {
	// Name is the namespaced parameter symbol ("Advection.u_wind").
	Name string
	// Owner is the owning component's namespaced prefix ("Advection").
	Owner string
	// Source is the `data_sources` key the parameter's update names.
	Source string
	// FileVariable is the source-file variable the binding names.
	FileVariable string
	// Cadence follows the SOURCE, not the parameter (CONFORMANCE_SPEC §5.7.2):
	// a source WITH a `temporal` block is time-varying → "discrete"; one
	// without is read once → "const".
	Cadence string
	// DataSource is the resolved `data_sources` entry.
	DataSource DataSource
	// UnitConversion is the binding's declared `unit_conversion` (§8.5), or nil.
	UnitConversion Expression
	// RecordsPerSample is the EFFECTIVE number of records the parameter
	// receives per query time, 1 or 2 (esm-spec §8.5.1): the binding's
	// `from.records_per_sample`, else the source's
	// `temporal.records_per_sample`, else 1. With 2 the field holds the record
	// at or before the query time and its successor, stacked along the
	// parameter's first dimension.
	RecordsPerSample int
}

LoaderField is a data-fed PARAMETER lowered to a flattened array input (esm-spec §8.5). From 1.0.0 a data source is not a component: a model consumes a source by declaring a parameter whose update is {kind: "data", source: <key>, from: {file_variable}} — the parameter IS the loaded field. Flatten records this descriptor per such parameter so a simulator can execute the source at its cadence and bind the resulting array into the RHS as a read-only input, keyed by the parameter’s namespaced name.

Source · Go docs