Function jacobian_compiled_indexed_into 

pub fn jacobian_compiled_indexed_into(
    cg: &CompiledGraph,
    node_params: &[Vec<f64>],
    x: &[f64],
    data: &mut Vec<f64>,
) -> Result<(), CoreError>

Compute the analytical Jacobian using a reusable row-major scratch buffer.

Callers with iterative solve loops can reuse data across iterations to reduce repeated heap allocation churn.

Errors

Returns CoreError::Eval if: x.len() is not an exact multiple of the graph’s coordinate dimensionality (GraphError::XBufferStrideMismatch); the graph’s nodes disagree on n_dims (GraphError::DimensionalityMismatch); or a node’s dataset_index is out of range for the recorded dataset_offsets (GraphError::DatasetIndexOutOfRange).