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Tracing analysis paths

The analysis path is the human-readable, step-by-step explanation the engine produces alongside a result. Where the criteria path is a list of criteria references and the calculation path is the engine's procedural steps, the analysis path is the prose explanation a user reads when they want to know why the engine reached a particular verdict. For the conceptual contrast between the three, see the comparison table in Criteria path.

Learning objectives
  • Locate the analysis path for any result
  • Diagnose a surprising result by walking the analysis path step-by-step
  • Recognize the most common diagnostic patterns and what each one points at

Where the worked examples live​

Reading an analysis path top-to-bottom is best learned against real engine output. The Module 1 worked examples each cover one perspective:

  • QD worked example — the Required-result analysis path for a 1,000 lb 1.1 PES → IHB ES under DCMA, showing how the engine reaches 1,250 ft.
  • DQ worked example — the same pair from the inverted side, showing how the engine reaches 52,734 lb allowable at 1,500 ft and why the governing criterion shifts.
  • PES/ES analysis paths — the side-level paths that resolve the analysis code (AGSU, IBD) one level above per-hazard math.

Read those for the mechanics. The rest of this page covers diagnostic use.

Diagnostic patterns​

When a result is surprising, open the analysis path on the result and walk the steps. The three patterns below cover most "why did the engine do that?" questions.

"The code is K18 even though I added a barricade"​

Look in the analysis path for where the engine evaluated the relationship code and the barricade check. The most common cause is related (parallel operating lines) instead of sameline — a barricade does not earn the K18 → K9 reduction across parallel lines. See Calculator: Barricading and the barricaded-related-vs-sameline exercise.

If the relationship is sameline, check whether the criteria path is on a barricaded variant at all (some Exposure Types — IBD, PTRD — do not earn barricaded reductions under DCMA).

"The governor flipped from blast to frag (or vice versa)"​

The Required result's analysis path contains the cross-hazard comparison explicitly. Find the line that says which value won — it will reference the per-hazard values produced upstream. The most common causes of a governor flip:

  • NEW crossed a threshold (typical: blast scales as NEW^(1/3); past ~30,000 lb 1.1, blast can overtake frag)
  • A barricade reduced blast but not frag, lifting frag into the governor seat
  • A type-code or attribute change pulled the engine onto a different criterion entry with a different mix of hazards

The Required path will show the comparison; the per-hazard paths show what each candidate's underlying calculation was.

"The analysis is empty / the pair is missing from results"​

If the analysis path is short and ends in NEW = 0, no QD required or similar, the engine had nothing to analyze — typically because explosives were not entered for any hazard division on the PES.

If the feature itself is missing from results entirely (not even an empty analysis), that is not an analysis-path issue — the engine never tried. Most common causes:

  • Feature is on a background layer instead of QD-visible
  • Multi-face feature has no front assigned (lands in Requires Analysis)
  • Explosive is missing on the PES, rather than returning no QD required like with 0 NEW, a blank entry will skip running the analysis