ZCtrlPar.txt

Purpose

ZCtrlPar.txt specifies the sequence time and probability truncation criteria for the simulation. These settings allow the analyst to limit computation by abandoning low-probability sequences and capping the maximum simulation time.

Location: Input/Scheduler/ZCtrlPar.txt inside the project directory. The file is part of the configuration fingerprint that guards checkpoint/resume — editing it between a checkpoint and a resume makes the resume refuse (by design).

CLI override

--truncation-time=<seconds> overrides the file's Truncation_time for a single run without editing the file — useful for sweeping mission times over the same case:

./adsidac --project-dir=<path> --input-deck=<deck>.i --truncation-time=1000

Resumed runs must repeat the override

The checkpoint does not store the CLI override. When resuming a checkpointed run that used --truncation-time, pass the same value on the resume command; a mismatch silently truncates resumed lineages at mixed times and produces a wrong tree with no error message.

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Early Termination Conditions

A sequence may be terminated before the simulation_end_time is reached under any of the following conditions:

1. The sequence probability falls below Truncation_probability.
2. An A_ENDSEQ_ alarm is actuated within the simulation.
3. A VSTOP non-response action is encountered.

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Input File Format

CtrlPar
Truncation_probability     truncation_probability
Truncation_time            simulation_end_time

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Parameter Reference

Parameter	Format	Range	Description
truncation_probability	Double	> 0.0	Probability threshold for sequence truncation. Any sequence whose probability drops below this value is terminated.
simulation_end_time	Double	> 0.0	Maximum simulation time in seconds. Must be less than or equal to the RELAP end time specified in the 200-series control cards.

RELAP end-time consistency

The simulation_end_time must not exceed the maximum end time entered in the RELAP input deck 200-series control cards. If it does, ADS-IDAC will attempt to advance beyond the RELAP simulation window, causing runtime errors.

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Sample Input

CtrlPar
Truncation_probability     1.0E-4
Truncation_time            6000.0

This sample sets a sequence probability truncation threshold of 10⁻⁴ and a maximum simulation time of 6000 seconds (100 minutes). Any sequence branch whose cumulative probability falls below 10⁻⁴ is terminated, and all branches are ended at 6000 seconds if still active.