Annex A.10 Comparison

This table compares this implementation with Table A.10, "Additional numerical examples for software validation purposes", from ISO 17507-1:2025.

Calculating Annex A.10 examples...

1. Published Annex A.10 MN_C value.
2. This implementation's MN_C minus the reference value.
3. Final range between the selected partial-mixture methane numbers before the inert correction is added.
4. Ternary systems used in the final calculated result.
5. Systems selected initially, then removed from the final weighted result because their contribution fell below the minimum threshold.

The spread values are an internal consistency indicator for the selected partial-mixture calculation. Low spread indicates that the selected systems have converged to very similar partial methane numbers before they are combined, so the weighted result is well determined.

ISO 17507-1:2025 Annex A.10 publishes only the reference methane numbers for these examples, not the underlying partial-system quantities or partial-system spreads used to obtain them. In this implementation, methods that move the result closer to some Annex A.10 values generally also produce larger final spreads. The Annex values are therefore used as diagnostic reference points, not as sole acceptance criteria for the optimizer.