Snng Workflow

CLI workflow for SNNG-only fitting.

Command: fit-snng-switching

Fit the SNNG switching model to a CSV or Excel table.

Arguments

Scientific choices

Flag	Required	Default	Help	Choices
--time-column	No	time	Select the time column. Example: --time-column time_ns.
--data-kind	Yes		Choose the input representation. Example: --data-kind polarization.	fraction, polarization, polarity-columns
--value-column	No		Select the fraction or polarization column. Example: --value-column Pz.
--polarity-columns	No		List per-domain polarity columns. Example: --polarity-columns d1 d2 d3.
--group-column	No		Fit each field, pulse, or sample separately. Example: --group-column field.
--initial-polarization	No		Override the first polarization value. Example: --initial-polarization -100.
--final-polarization	No		Override the final polarization plateau. Example: --final-polarization 100.
--tail-fraction	No	0.1	Use this final fraction of rows to estimate the polarization plateau. Example: --tail-fraction 0.2.
--clip-fraction	No	False	Clip normalized values to [0,1]. Example: --clip-fraction.
--fixed	No		Fix a parameter; KAI t0 can be inferred from the 63.2% crossing. Example: --fixed t0.
--bounds	No		Override positive fit bounds. Example: --bounds kai.n=0.5:8.
--initial	No		Override an initial guess. Example: --initial kai.t0=5.
--sweep	No		Conditionally refit a parameter range or list. Example: --sweep kai.n=1:6.
--fit-nls-amplitude	No	False	Fit NLS amplitude A instead of fixing A=1. Example: --fit-nls-amplitude.
--starts	No	12	Set the number of optimization starts. Example: --starts 24.
--seed	No	0	Set the multi-start random seed. Example: --seed 7.
--loss	No	linear	Choose the least-squares loss. Example: --loss soft_l1.	linear, soft_l1, huber, cauchy, arctan
--thickness	No		Provide SNNG thickness to derive a physical factor. Example: --thickness 100e-9.
--wall-velocity	No		Provide SNNG wall velocity to derive N_infinity. Example: --wall-velocity 2.5.
--nucleation-density	No		Provide SNNG N_infinity to derive wall velocity. Example: --nucleation-density 1e12.
--time-unit	No	input units	Label plot time axes without rescaling values. Example: --time-unit ps.

Input and file selection

Flag	Required	Default	Help	Choices
--input	Yes		Read a CSV or Excel table. Example: --input switching.xlsx.

Outputs and plots

Flag	Required	Default	Help	Choices
--sheet	No	0	Select an Excel sheet by index or name. Example: --sheet pulse_1.
--figure-dpi	No	180	Set PNG plot resolution. Example: --figure-dpi 300.
--output	No		Set the workbook or CSV-directory name inside the unique run folder. Example: --output switching_fits.xlsx.
--detail-format	No		Optional detail format (default: Parquet; legacy: CSV).	parquet, csv

Execution

Flag	Required	Default	Help	Choices
--execution	No	auto	Execution backend; unsupported backends fall back to serial with a logged reason.	auto, serial, threads, processes
--workers	No	0	Frame workers: auto or N (default: auto).
--chunk-size	No	0	Maximum in-flight frames: auto or N.

Storage and cache

Flag	Required	Default	Help	Choices
--output-profile	No	standard	Artifact profile (default: standard).	standard, minimal, full, legacy

Diagnostics and compatibility

Flag	Required	Default	Help	Choices
-h, --help	No		show this help message and exit
--help-all, --all-flags	No		Show every option, grouped by purpose.

Common Runtime and Presentation Arguments

These are shared workflow-level CLI flags added before command-specific options, covering runtime context (engine/input/storage) and output presentation/export behavior.

Each command table above includes its shared and inherited options.