Function read_gridfm_dataset 

pub fn read_gridfm_dataset(
    dir: impl AsRef<Path>,
    scenario: i64,
) -> Result<GridfmRead>

Read one scenario from a gridfm dataset on disk and rebuild a Network. The inverse of write_gridfm_dataset.

dir is resolved leniently: the leaf raw/ directory holding the parquet files, a <case>/ directory with a raw/ child, or a parent directory with exactly one */raw/ child all work. base_mva and the case name come from gridfm_meta.json (a missing manifest defaults base_mva to 100 and warns).

Errors

Propagates read_gridfm_network plus any filesystem / Parquet read error.