Analysis Tab¶

The Analysis tab is the main working area. It loads experiment data, runs the analysis every time a relevant control changes, and shows the intermediate and final plots.

Experiment Controls¶

Control	What it does
Load experiment...	Opens a folder picker. Choose the experiment directory containing signal files and configuration.
Save config	Writes a per-experiment hopki.toml containing only fields that differ from the inherited campaign/default configuration. This is useful after editing dimensions or accepting estimated distances.
Revert config	Reloads configuration from disk and discards live edits made in the GUI.
Directory label	Shows the currently loaded experiment path.
Editable fields	The text fields for bar, specimen, and damping values. Editing a field and leaving it reruns the analysis. See Parameters for every field.
Derived readout	Shows tpp, which is read from the signal time column, and warns when x1 or x2 was auto-estimated.
Re-estimate x1, x2	Recomputes both gauge distances from the loaded signals and replaces the current values. The status message reports x1 correlation and x2 signal-to-noise ratio.
Pick x2 (2 clicks)	Lets you set x2 manually from the Signals plot. Click the incident pulse arrival, then the transmitted pulse arrival. Hopki computes x2 from the time difference and the acquisition delay.

Parameter Controls¶

Control	What it does
Theme	Switches the GUI between the available visual themes.
invert signal polarity	Negates both input channels before analysis. Use it when the incident pulse should be negative but appears positive.
Poisson nu	Poisson ratio used to build the Bancroft dispersion table. Range: 0.20 to 0.35; default: 0.29.
reflect shift	Integer sample shift applied to the reflected pulse after dispersion correction. Range: -50 to 50; default: 0. Positive values delay the reflected pulse.
Slider below reflect shift	A faster way to adjust the same reflected-pulse shift. It stays synchronized with the numeric field.
tim_cut readout	Displays the pulse-start time set by the draggable marker on the Signals plot.

Graph Controls¶

The Graphs checklist toggles plot visibility. It does not change the analysis; it only hides or shows plots to make the tab easier to scan.

Plot	What to inspect
Signals	Raw incident/reflected and transmitted voltage signals. Drag the vertical line here to set tim_cut.
Windowed pulses	The incident, reflected, and transmitted pulse windows cut from the raw signals.
Corrected + aligned	Pulses after dispersion/damping correction, with the reflected pulse shifted by reflect shift.
Force equilibrium	f_in and f_out. These should be compared when tuning alignment and checking whether the analysis window is reasonable.
Force difference	f_in - f_out. Drag the shaded region to report mean force difference over a selected time interval.
Stress-strain	Engineering and true stress-strain curves from the current analysis.

Bottom Buttons¶

Button	What it does
sigma-epsilon -> Figures	Sends the current true stress-strain curve to the Figures tab.
Export results...	Opens an output-folder picker and writes MATLAB-style output files such as inc_puls, ref_corr, f_in, s_e_eng, and s_e_true.

Status Line¶

The status line reports the current striker velocity estimate and point count after a successful run. If a field is invalid or a pulse window is out of range, the same area shows the error.