SurveyFit (Reference)

Overview

This page provides a detailed reference for the SurveyFit software interface, controls, dialogs, command-line interface, project files, solver options, and user-visible diagnostics.

For installation, workflow guidance, and interpretation of calibration results, see the User Guide. For worked examples, see Examples.

Main Window

Figure 1. Main SurveyFit application window.

The SurveyFit main window consists of:

• a menu bar
• a toolbar
• a tabbed workspace
• an Issues panel
• a Log panel
• a status bar

The tabbed workspace is the primary area for editing parameters, measurements, solve settings, and results. The Issues panel reports configuration and validation problems. The Log panel records execution and support messages.

Main Window Layout

Region	Description
Menu bar	Provides access to project, data, solve, view, and help commands.
Toolbar	Provides shortcut access to common project and solve commands.
Workspace tabs	Main editing and results area. Tabs include Parameters, Measurements, Solve, and Results.
Issues panel	Docked panel listing configuration and validation issues.
Log panel	Docked panel listing application and solve messages.
Status bar	Displays current SysCAD connection state, project state, solve progress, results state, and licensing state.

Status Bar

The status bar displays short state summaries for the active application session.

Indicator	Meaning
SysCAD: Project not selected	No SysCAD project has been configured for the current SurveyFit project.
SysCAD: Configured	A SysCAD project has been configured, but SurveyFit is not currently connected to an active SysCAD session.
SysCAD: Connected	SurveyFit is currently connected to the active SysCAD application through the SysCAD COM automation interface.
Iter: - Current: - Best: -	Displays the current solve iteration together with the current objective value and the best objective value found so far. A value of - indicates that no solve results are currently available.
License: Licensed	A valid SurveyFit license is installed.
License: Demo Mode	SurveyFit is operating in demonstration mode. See Demo Mode.
Results out of date	The current results no longer correspond to the present project configuration.

Menus and Toolbar

Menu Bar

The main menu bar contains the following top-level menus:

• File
• Edit
• Data
• Solve
• View
• Help

File Menu

The File menu contains project-level file operations.

Command	Description	Notes
New Project	Creates a new SurveyFit project.	Resets the current project state.
Open Project...	Opens an existing SurveyFit project file.	Uses the .sfit project format.
Save Project	Saves the current project.	Writes the current project to the existing .sfit file without prompting for a filename.
Save Project As...	Saves the current project to a new file.	Prompts for a new path and filename, and asks for confirmation before replacing an existing file.
Exit	Closes the SurveyFit application.	May prompt if the current project has unsaved changes.

Edit Menu

The Edit menu contains application-level configuration commands.

Command	Description	Notes
Preferences...	Opens the Preferences dialog.	Controls application-level settings rather than project settings. See Preferences Dialog.

Data Menu

The Data menu contains commands related to parameter and measurement data import, export, and validation.

Command	Description	Notes
Import Parameters CSV...	Imports parameter data from a CSV file.	Used to populate or update the Parameters table.
Import Measurements CSV...	Imports measurement data from a CSV file.	Used to populate or update the Measurements table.
Export Parameters CSV	Exports parameter data to CSV.	Uses the current parameter table content.
Export Measurements CSV	Exports measurement data to CSV.	Uses the current measurement table content.
Validate Data	Runs project validation checks.	Validation results appear in the Issues panel and related messages or dialogs.

Solve Menu

The Solve menu contains commands related to solve execution and solver control.

Command	Description	Notes
Start	Starts the parameter estimation solve.	Uses the current project configuration.
Pause	Pauses the active solve.	Only available when a solve is running.
Resume	Resumes a paused solve.	Only available when a solve is paused.
Stop	Stops the active solve.	Requests cancellation of the current run.
Close SysCAD	Closes the active SysCAD session.	Closes the current SysCAD application session used by SurveyFit.
Clear Results	Clears current solve results.	Marks results as unavailable or out of date.
Copy Command	Copies a command-line solve command to the clipboard.	Generates a SurveyFitCmd command corresponding to the current project configuration. See Command Line Interface.

View Menu

The View menu contains commands related to panel visibility and user interface display.

Command	Description	Notes
Issues	Shows or hides the Issues panel.	Dock visibility control.
Log	Shows or hides the Log panel.	Dock visibility control.
Reset Layout	Restores the default application layout.	Resets the arrangement of docked panels and related window layout state.

Help Menu

The Help menu contains documentation, support, system information, licensing, and about commands.

Command	Description	Notes
Online Documentation	Opens the online SurveyFit documentation landing page.	External documentation link.
Copy System Info	Copies system information to the clipboard.	Intended for support and troubleshooting.
Open Log Folder	Opens the application log folder.	Intended for support and troubleshooting.
License	Opens the License dialog.	Used to inspect licensing state. See License Dialog.
About SurveyFit...	Opens the About dialog.	Displays application and build information. See About SurveyFit Dialog.

Toolbar

The toolbar provides shortcut access to frequently used commands. Toolbar actions correspond to menu commands or other user-visible actions exposed by the main window.

Toolbar Action	Description	Notes
New Project	Creates a new project.	Equivalent to File -> New Project.
Open Project	Opens an existing project.	Equivalent to File -> Open Project....
Save Project	Saves the current project.	Equivalent to File -> Save Project.
Import CSV	Imports project data from CSV.	Used for parameter and measurement CSV import actions.
Export CSV	Exports project data to CSV.	Used for parameter and measurement CSV export actions.
Validate Data	Runs project validation checks.	Equivalent to Data -> Validate Data.
Start	Starts the solve.	Equivalent to Solve -> Start.
Pause	Pauses the solve.	Equivalent to Solve -> Pause.
Resume	Resumes the solve.	Equivalent to Solve -> Resume.
Stop	Stops the solve.	Equivalent to Solve -> Stop.
Clear Results	Clears current solve results.	Equivalent to Solve -> Clear Results.
Copy All	Copies the full solve report to the clipboard.	Copies a plain-text report of the current solve results and summary information.

Workspace Tabs

Parameters Tab

Figure 2. Parameters tab.

The Parameters tab defines the adjustable model parameters used in the regression. Each row in the parameter table corresponds to one parameter associated with a SysCAD tag.

Parameter Table Columns

Column	Description	Notes
On	Enables or disables the parameter for the current solve.	Disabled parameters are excluded from regression.
Order	Display order of the parameter row.	Used for table ordering. Has no solver effect.
Name	User-visible parameter name.	May be imported or manually assigned.
Tag	SysCAD tag associated with the parameter.	Used to write the parameter value during optimisation.
Lower	Lower bound applied during regression.	Must be less than Upper.
Upper	Upper bound applied during regression.	Must be greater than Lower.
Transform	Internal parameter transform used during optimisation.	Allowed values are Linear, Log, and Sigmoid.
Initial Value	Starting value used when the solve begins.	Typically taken from the current project or current SysCAD state.
Current Value	Current parameter value in the active project state.	Updated as the project state changes.
Best Value	Best parameter value found during the solve.	Updated as improved solutions are found.

Bounds

The Lower and Upper columns define the allowable parameter range during optimisation. These bounds are enforced together with the selected transform.

Transform Options

The Transform column specifies the internal parameter transform used during optimisation. These transforms allow SurveyFit to enforce positivity or finite bounds while solving in an internal variable.

Transform	Notes
Linear	Use when the parameter behaves well on its natural scale. Does not require special handling. This is the simplest option. Usually appropriate when the parameter range is moderate and the bounds are mainly advisory rather than numerically critical.
Log	Use for strictly positive parameters. Especially useful when the parameter may vary over a wide range. Often a good choice when multiplicative changes are more natural than additive changes. Should not be used if zero or negative values must remain possible.
Sigmoid	Use when the parameter must remain strictly between the specified Lower and Upper bounds. Useful when the bounds are physically meaningful and must always be enforced during optimisation. Can make the problem more nonlinear near the bounds. Best used when those limits are genuinely important.

Measurements Tab

Figure 3. Measurements tab.

The Measurements tab defines the plant survey measurements used as regression targets. Each measurement row corresponds to one user-visible measurement linked to a SysCAD tag.

Measurement values, uncertainty information, and fit residuals are displayed here.

Measurement Table Columns

Column	Description	Notes
On	Enables or disables the measurement for the current solve.	Disabled measurements are excluded from the objective function.
Order	Display order of the measurement row.	Used for table ordering. Has no solver effect.
Name	User-visible measurement name.	May be imported or manually assigned.
Tag	SysCAD tag associated with the measurement.	Used to evaluate the simulated value.
Measured Value	Target plant survey value.	Used as the regression target.
Error Model	Error model applied to the measurement.	Allowed values are Fixed and Whiten (PSD). See Error Model Options below.
SD	Standard deviation associated with the measurement.	Editable for Fixed rows. Calculated and locked for Whiten (PSD) rows.
Estimated Value	Simulated value predicted by the flowsheet model.	Updated from the active model evaluation.
Residual	Difference between the estimated value and the measured value.	Updated from the active model evaluation.
Std Residual	Standardised residual, calculated as the residual divided by the measurement standard deviation.	Unitless quantity used in residual diagnostics and histogram plots.

Error Model Options

The Error Model column specifies how measurement uncertainty is treated for the row.

Error Model	Use and Notes
Fixed	Use when the measurement standard deviation is entered directly by the user. The SD field remains editable for this option. This is the standard choice for ordinary measurements where a single fixed uncertainty value is appropriate.
Whiten (PSD)	Use for particle size distribution measurements. For this option the SD value is calculated automatically rather than entered directly in the table. This model applies an empirical sizing-data uncertainty rule based on the measured size fraction value.

Whiten (PSD) Model

For the Whiten (PSD) error model, the standard deviation for each size fraction measurement is calculated from the measured size fraction value [math]\displaystyle{ x_i }[/math], expressed in percent units.

[math]\displaystyle{ \mathrm{SD}_i = \min\left(1.0,\ 0.1 + \frac{x_i}{10}\right) }[/math]

where:

• [math]\displaystyle{ x_i }[/math] is the measured size fraction value in percent
• [math]\displaystyle{ \mathrm{SD}_i }[/math] is the standard deviation assigned to that size fraction measurement

The Whiten (PSD) option is intended for sizing data, where the measurement uncertainty varies with the size fraction value rather than remaining fixed across all rows. When this option is selected, the SD field is calculated automatically and is not edited directly by the user.

Solve Tab

Figure 4. Solve tab.

The Solve tab contains the controls and status displays used during solve execution. It is the primary tab used while a solve is running.

Solve Controls

Control	Description	Notes
Start	Starts the parameter estimation solve.	Uses the current project configuration.
Stop	Stops the active solve.	Requests cancellation of the current run.
Pause	Pauses the active solve.	Only meaningful while a solve is running.

Solve Status Display

The status strip above the objective history chart displays current solve state and summary metrics.

Item	Description	Notes
Results out of date	Indicates that the current results no longer correspond to the present project configuration.	Displayed when the project has changed since the last valid results state.
Objective	Current objective value for the active solve.	Displayed while solve results are available.
Best	Best objective value found so far.	Displayed while solve results are available.
Elapsed	Elapsed solve time.	Displayed while a solve is running or after results are available.
iter/s	Approximate solve iteration rate.	Displayed while a solve is running.

Objective History Chart

The objective history chart displays the regression objective value over the course of the solve.

Item	Description	Notes
Chart Area	Displays the objective history for the current solve.	Updated during solve execution when objective history is available.
X-axis	Solve iteration or evaluation index.	Represents progression through the current solve.
Y-axis	Objective value.	Displays the regression objective corresponding to each recorded solve point.
No objective history	Placeholder text shown when no objective history is available.	Displayed before a solve has been run or after results have been cleared.
Scale	Indicates the current Y-axis scaling mode.	The displayed indicator shows whether logarithmic scaling is active.
Log Y axis	Toggles logarithmic scaling of the chart Y-axis.	Intended to improve display when objective values vary over a wide range.

SysCAD Configuration

The SysCAD Configuration group controls the SysCAD project used during solving.

Item	Description	Notes
Project	Displays the configured SysCAD project path.	The selected project is used for solve execution.
Browse...	Opens a file selection dialog for the SysCAD project.	Used to choose or replace the configured SysCAD project.
Reset SysCAD between evaluations	Resets the SysCAD session before each evaluation.	May improve robustness at the cost of solve speed.
Save SysCAD Project after solve	Writes fitted values back to the SysCAD project after a solve.	Saves the final fitted state to the SysCAD project.

Solver Configuration

The Solver Configuration group displays a compact summary of the current solver settings.

Item	Description	Notes
Algorithm	Displays the configured optimisation algorithm.	Shown in the solver summary line.
Loss	Displays the configured loss formulation.	Shown in the solver summary line.
Tol	Displays the configured tolerance value.	Shown in the solver summary line.
Cont	Displays the configured continuation or pass setting.	Shown in the solver summary line.
Log	Displays the configured logging detail.	Shown in the solver summary line.
Solver Settings...	Opens the Solver Settings dialog.	Used to configure detailed solve options.

Solve Event Log

The lower table on the Solve tab displays solve event messages.

Column	Description
Time	Time associated with the logged event.
Event	Description of the solve event.

Results Tab

Figure 5. Results tab.

The Results tab provides graphical and summary diagnostics for the current solve results. It is used to review the agreement between measured and estimated values and to inspect the distribution of standardised residuals.

Summary

The Summary group displays a compact text summary of the current results and solver configuration.

Item	Description	Notes
Measurements	Number of measurements included in the current results summary.	Displayed as a count.
Objective	Current objective value for the displayed results.	Shown in the summary line.
RMS Std Residual	Root-mean-square value of the standardised residuals.	Summary statistic for the overall residual magnitude.
Max Abs Std Residual	Maximum absolute standardised residual.	Identifies the largest standardised residual magnitude in the current results.
Algorithm	Solver algorithm associated with the current results.	Displayed in the secondary summary line.
Loss	Loss formulation associated with the current results.	Displayed in the secondary summary line.
Passes	Continuation or pass count associated with the current results.	Displayed in the secondary summary line.

Parity Plot

The parity plot compares measured values with estimated values for the current results.

Item	Description	Notes
Chart Title	Measured vs Estimated (Parity)	Displayed above the plot.
X-axis	Measured Value	Uses the current measurement values included in the results.
Y-axis	Estimated Value	Uses the corresponding model-predicted values.
Parity Line	Diagonal reference line representing perfect agreement.	Used as a visual reference only.
Data Points	Individual measurement comparisons.	Each point represents one measurement included in the results.
Hover Information	Displays measurement-specific details for a plotted point.	Includes fields such as measurement name, tag, measured value, estimated value, and standardised residual where available.

Parity Plot Options

The Results tab provides display options for the parity plot.

Option	Description	Notes
Log axes	Displays the parity plot using logarithmic axes.	Intended for measurements spanning a wide numerical range.
Equal axes	Uses the same scale on both axes.	Helps visual comparison against the parity line.
Non-positive value exclusion notice	Indicates that points with non-positive values are excluded when log axes are enabled.	The message reports how many points were excluded.

Residual Histogram

The residual histogram displays the distribution of standardised residuals for the current results.

Item	Description	Notes
Chart Title	Std Residual distribution	Displayed above the histogram.
X-axis	Std Residual	Standardised residual values.
Y-axis	Count	Number of measurements falling within each histogram bin.
Bars	Histogram bins of standardised residual values.	Represents the residual distribution for the current results.
Mean	Mean of the standardised residuals.	Displayed as summary text on the chart.
Std	Standard deviation of the standardised residuals.	Displayed as summary text on the chart.

Results Tab Behaviour

Behaviour	Description
Results source	The Results tab displays the current stored results for the active project.
Out-of-date results	If the project configuration changes after a solve, the results may no longer correspond to the present project state.
Chart updates	The parity plot and residual histogram update when valid results are available.

Dialogs

This section documents user-visible dialogs and prompts exposed by SurveyFit.

Dialog Inventory

Dialog	Opened From	Purpose	Key Fields / Actions
About SurveyFit	Help menu	Displays product and version information for the running application.	Product name, version, build date, website, copyright, Copy System Info.
Preferences	Edit menu	Configures application-level settings.	Startup behaviour and SysCAD COM timeout.
Solver Settings	Solve tab	Configures detailed solver behaviour.	Algorithm, tolerances, logging, Jacobian, robust loss, step control, continuation passes.
License	Help menu	Displays license file and current license status.	License file path, Browse, Check License, status fields, Show Details / Hide Details.
License Details	License dialog	Displays detailed license information.	Detailed license text including Site Code and raw status values.
Unsaved Changes Prompt	Project close or replace actions	Confirms how unsaved project changes should be handled.	Save, Don't Save, Cancel.
Worker Error Dialog	Solve or SysCAD execution failure	Reports worker or solve-related failures.	Error message and follow-up action.
Crash Dialog	Unexpected application failure	Reports an unexpected application error.	Error summary and support-related action.

About SurveyFit Dialog

The About SurveyFit dialog displays product identification and build information for the running application.

Item	Description
Product name	Displays the application name.
Version	Displays the application version and build architecture.
Build date	Displays the application build date and time.
Website	Displays the product website.
Copyright	Displays the copyright notice for Met Dynamics Pty Ltd.
Copy System Info	Copies system and application information to the clipboard.

Preferences Dialog

The Preferences dialog provides application-level settings that persist independently of the current SurveyFit project.

Item	Description
Load last project on startup	Controls whether SurveyFit automatically reopens the most recently used project when the application starts.
SysCAD COM operation timeout (seconds)	Specifies the timeout used for SysCAD COM operations.

Solver Settings Dialog

The Solver Settings dialog provides detailed configuration of solve behaviour. The dialog is organised into grouped sections.

Algorithm

Item	Description
Algorithm	Selects the optimisation algorithm used for the solve. The current implementation provides the Trust Region method.
Maximum model evaluations	Specifies the maximum number of model evaluations allowed during the solve.
Trust region regularization	Enables an additional stabilisation option for the Trust Region method.

The Trust Region method is a robust general-purpose algorithm for nonlinear parameter estimation with bounded parameters. It is well suited to SurveyFit because parameter fitting problems commonly include lower and upper bounds, nonlinear model responses, and interactions between parameters.

The Trust region regularization option can improve solve stability when the data do not strongly distinguish between different parameter combinations, or when several parameters influence the fit in similar ways. In these situations the solve may otherwise become less stable or make poor progress. This option is usually most useful for difficult or highly coupled fitting problems.

Tolerances

Item	Description
Stop when parameters stop changing	Tolerance controlling termination when parameter updates become sufficiently small.
Stop when fit stops improving	Tolerance controlling termination when improvement in the fit becomes sufficiently small.
Stop when solution is stationary	Tolerance controlling termination when the solution becomes effectively stationary.

Logging

Item	Description
Log detail	Selects the amount of solve logging detail recorded during execution.

Log Detail Options

Option	Notes
Minimal	Records only the most important solve messages. Use when a short log is preferred and detailed troubleshooting information is not needed.
Normal	Records a moderate amount of solve information. Suitable for routine use when some diagnostic detail is useful without producing an overly long log.
Detailed	Records the most detailed solve information. Use when investigating solve behaviour, validation issues, or SysCAD communication problems.

Jacobian

Item	Description
Derivative method	Selects the method used to approximate derivatives.
Parameter scaling	Selects the scaling method used for the solver variables.
Positive scalar ...	Additional scaling control associated with the selected parameter scaling mode.

Robust Loss

Item	Description
Outlier handling	Selects how strongly large residuals are allowed to influence the fit.

The Outlier handling setting controls how SurveyFit treats measurements that differ strongly from the rest of the data. This can be important when one or more measurements are inconsistent, affected by sampling error, or otherwise behave like outliers.

Option	Notes
Standard least squares (recommended)	Uses ordinary least squares. This is the default and is usually appropriate when the survey data are internally consistent and the measurement uncertainties are realistic.
Robust: Soft L1	Reduces the influence of large residuals in a smooth way. This is a good general-purpose robust option when a few measurements may be inconsistent but should not be ignored completely.
Robust: Huber	Behaves like ordinary least squares for small residuals and reduces the influence of larger residuals beyond a threshold. Useful when most measurements are reliable but a small number may be moderately inconsistent.
Robust: Cauchy	Strongly reduces the influence of very large residuals. Useful when a few measurements appear highly inconsistent, but it can also make the solve harder to stabilise and should be used more cautiously.

Step Control

Item	Description
Use custom derivative step size	Enables manual control of the derivative step size.
Derivative step size	Specifies the derivative step size when custom step control is enabled.

Continuation (Stability Passes)

Item	Description
Enable stability passes	Enables continuation or stability passes after the main solve.
Maximum passes	Specifies the maximum number of continuation passes.
Stop passes when improvement is small	Specifies the threshold below which continuation passes stop due to small improvement.

License Dialog

The License dialog displays the current license file, the current license status, and optional detailed license information.

License File Section

The License File section is used to select and validate the current SurveyFit license file.

Item	Description
License file	Displays the current license file path.
Browse...	Opens a file selection dialog for choosing a license file.
Check License	Validates the current license file and updates the displayed status.

Status Section

The Status section displays the current interpreted license state.

Item	Description
License status	Displays the current license state, such as Licensed.
Licensed to	Displays the licensed user or organisation.
Expiry date	Displays the license expiry date.
Days remaining	Displays the number of days remaining until expiry.
Show Details	Expands the dialog to display the License Details section.
Hide Details	Collapses the License Details section.

License Details Section

When details are shown, the dialog displays a plain-text License Details panel containing the detailed parsed license information.

Item	Description
Licensing	Header line for the detailed license information block.
License file	Displays the license file path used for the current check.
License status	Displays the detailed license status value.
Product name	Displays the licensed product name.
Product version	Displays the licensed product version.
Build date	Displays the licensed build date and time.
Internal revision	Displays the internal revision value recorded in the license details.
License location	Displays the resolved license file location.
Site code	Displays the Site Code associated with the current machine or license context.
Required authorisation	Displays the product or authorisation target required by the license.
Raw status	Displays the raw license status value.
Issued to	Displays the licensed user or organisation.
Expiry date	Displays the license expiry date.
Days left	Displays the remaining license duration in days.
Copy Details	Copies the detailed license information to the clipboard.

Unsaved Changes Prompt

The unsaved changes prompt appears when the application needs to confirm how modified project data should be handled before closing or replacing the current project.

Action	Description
Save	Saves the current project changes before continuing.
Don't Save	Discards the current unsaved changes and continues.
Cancel	Cancels the pending action and returns to the application.

Worker Error and Crash Dialogs

SurveyFit may present dialog-based error reporting when background workers fail or when unexpected application errors occur.

Dialog Type	Description
Worker Error Dialog	Displays a solve or worker-related error message when a background task fails.
Crash Dialog	Displays an unexpected application error and provides information relevant to support and troubleshooting.

Issues and Logging

Issues Panel

The Issues panel displays structured project issues detected during validation and runtime checks. It is intended to identify problems in project configuration that may prevent a solve from running correctly or may make the current project state incomplete or inconsistent.

Issues Table

Column	Description
Severity	Severity classification for the issue.
Message	User-visible issue description.
Source	Project area or table associated with the issue.
Row	Row index associated with the issue, where applicable.
Column	Column associated with the issue, where applicable.

Issue Behaviour

Aspect	Description
Purpose	Reports project configuration and validation issues.
Scope	Parameters, measurements, project file state, solver configuration, SysCAD configuration, and related validation checks.
Row / column references	When available, these identify the specific table location associated with the issue.
Solve impact	Some issues may block solve execution, while others may indicate warnings or incomplete configuration.

Typical issue categories include:

• parameter configuration errors
• measurement configuration errors
• missing or invalid tags
• invalid bounds or missing uncertainty data
• project-level validation issues
• SysCAD configuration issues

Log Panel

The Log panel records plain-text application and solve messages in chronological order. It is used to review project activity, solve progress, validation messages, and support-related output.

The panel is presented as a scrollable text log rather than as a structured table.

Typical log content includes:

• project open and save messages
• data import and export messages
• SysCAD project selection and connection messages
• solve start, pause, resume, and stop messages
• validation messages
• warning and error messages
• support command output

The Log panel is primarily intended for troubleshooting, solve review, and support.

Validation and Error Conditions

SurveyFit validates project data before and during solve execution. Errors and warnings may appear in the Issues panel, Log panel, message dialogs, or CLI output.

Validation and Error Categories

Category	Description	Where Reported
Project configuration	Problems with overall project state or required inputs.	Issues panel, dialogs, CLI output
Parameters	Invalid bounds, missing tags, or related parameter problems.	Issues panel, dialogs
Measurements	Missing values, missing SD, invalid error model data, or related measurement problems.	Issues panel, dialogs
CSV exchange	Import or export data mismatch or invalid file content.	Dialogs, log output
SysCAD connectivity	SysCAD connection or runtime communication failures.	Log panel, dialogs, status bar
Solve execution	Runtime solve failure, cancellation, or invalid solver state.	Log panel, dialogs
Licensing / demo mode	Missing or invalid license state and demo-mode restrictions.	License dialog, dialogs, CLI output

Common Validation Conditions

Condition	Where Reported	Meaning / Effect
Lower bound greater than upper bound	Issues panel, dialogs, or CLI output	Parameter configuration is invalid and may block solve execution.
Missing SD	Issues panel, dialogs, or CLI output	Measurement uncertainty is incomplete and may block solving.
Missing or invalid SysCAD tag	Issues panel, log, or dialogs	Parameter or measurement cannot be evaluated correctly.
Failed SysCAD connectivity	Status bar, log, dialogs	SurveyFit cannot communicate correctly with the active SysCAD session.
Flowsheet evaluation failure	Log panel, dialogs, solve state	Model evaluation fails or solve progress is interrupted.
Demo-mode restriction	Dialogs, CLI output, license state	Command may be blocked or limited under demo mode.

Exact message wording should be preserved where the UI exposes stable and meaningful strings.

Project File Format

SurveyFit projects are stored using the .sfit file format.

A .sfit file stores the current SurveyFit project, including its configuration and results state, so that it can be reopened in a later session.

Command Line Interface

SurveyFit provides a command-line interface through the SurveyFitCmd.exe application.

The command-line interface is used to validate a SurveyFit project or run a solve from the console. Practical examples belong on the Examples page.

Executable and Command Structure

The command-line interface uses the following top-level syntax:

SurveyFitCmd.exe [-h] {solve,validate} ...

The available subcommands are:

• solve
• validate

General help is displayed with:

SurveyFitCmd.exe --help

Command-specific help is displayed with:

SurveyFitCmd.exe solve --help

SurveyFitCmd.exe validate --help

CLI Command Inventory

Command	Purpose	Notes
solve	Runs a solve using a SurveyFit project file.	Optional CSV override files may be supplied before solving.
validate	Validates a SurveyFit project and optional CSV override files without solving.	Checks project structure, table data, and SysCAD configuration without running the optimiser.

Solve Command

The solve command runs a SurveyFit solve from a project file. Optional CSV override files may be applied before solving, and the solved project may optionally be written to a new .sfit file.

General syntax:

SurveyFitCmd.exe solve --project PROJECT [--params CSV] [--meas CSV] [--save PROJECT] [--license PATH]

Option	Description	Notes
-h, --help	Displays help for the solve command.	Standard command help output.
--project PROJECT	Specifies the SurveyFit project file to solve.	Uses a .sfit project file.
--params CSV	Applies an optional parameters CSV override before solving.	Used to override parameter enable states or related parameter data for the current invocation.
--meas CSV	Applies an optional measurements CSV override before solving.	Used to override measurement values or related measurement data for the current invocation.
--save PROJECT	Saves the solved project to the specified output path.	The saved project is always written as .sfit.
--license PATH	Applies an optional license file override for the current invocation.	If omitted, the shared persisted license path is used.

Validate Command

The validate command checks the project structure, table data, SysCAD configuration, and optional CSV overrides without solving.

General syntax:

SurveyFitCmd.exe validate --project PROJECT [--params CSV] [--meas CSV] [--license PATH]

Option	Description	Notes
-h, --help	Displays help for the validate command.	Standard command help output.
--project PROJECT	Specifies the SurveyFit project file to validate.	Uses a .sfit project file.
--params CSV	Applies an optional parameters CSV override before validation.	Used to validate parameter overrides without modifying the base project file.
--meas CSV	Applies an optional measurements CSV override before validation.	Used to validate measurement overrides without modifying the base project file.
--license PATH	Applies an optional license file override for the current invocation.	If omitted, the shared persisted license path is used.

CLI Examples

Representative command-line examples include:

Action	Command
Solve using project file	SurveyFitCmd.exe solve --project project.sfit
Solve with parameter overrides	SurveyFitCmd.exe solve --project project.sfit --params params.csv
Solve with measurement overrides	SurveyFitCmd.exe solve --project project.sfit --meas measurements.csv
Solve and save solved project	SurveyFitCmd.exe solve --project project.sfit --save solved.sfit
Validate measurement inputs	SurveyFitCmd.exe validate --project project.sfit --meas measurements.csv
Solve with explicit license file	SurveyFitCmd.exe solve --project project.sfit --license C:\Path\MetDynamics.lic
Validate with explicit license file	SurveyFitCmd.exe validate --project project.sfit --license C:\Path\MetDynamics.lic

CLI Outputs and Behaviour

The command-line interface may produce the following user-visible outputs:

• help text
• validation results
• solve progress messages
• status summaries
• warning messages
• error messages
• demo-mode restriction messages

Demo Mode

When no valid license is installed, SurveyFit operates in Demo Mode. In this state the application remains usable, but selected actions and solve sizes are restricted.

Demo Mode Indicators

Location	Behaviour
Main window title	Displays the suffix [Demo Mode].
Status bar	Displays License: Demo Mode.
CLI	Prints Unlicensed - Demo Mode when the license state affects command behaviour.

Solve Limits

Demo Mode restricts the size of problems that can be solved.

Limit	Behaviour
Variable parameters	A solve is blocked if more than 3 variable parameters are selected.
Measurements	A solve is blocked if more than 20 measurements are selected.

Representative limit messages include:

• Demo Mode limit exceeded: <n> variable parameters selected, maximum is 3.
• Demo Mode limit exceeded: <n> measurements selected, maximum is 20.
• This project exceeds Demo Mode solve limits.

GUI Behaviour in Demo Mode

In the GUI, Demo Mode allows the application to be opened and configured, but selected actions may be restricted.

Area	Behaviour in Demo Mode
Status display	Demo Mode is shown in the status bar and window title.
Solve execution	Solve requests are blocked when the configured project exceeds the Demo Mode limits.
Save-related prompts	Save may be unavailable in some situations, with user-visible messaging such as Save is disabled in Demo Mode.

Command-Line Behaviour in Demo Mode

In the command-line application, Demo Mode restrictions are enforced in the same general way as in the GUI.

Area	Behaviour in Demo Mode
CLI status output	Prints a concise demo-mode status message when licensing affects command behaviour.
Solve execution	Solve requests are blocked when the configured project exceeds the Demo Mode limits.
Exit behaviour	Demo-limit failures are treated as solve/demo-limit errors.

Terminology

This section defines selected interface terms that are used repeatedly throughout SurveyFit.

Term in Interface	Meaning
SD	Standard deviation associated with a measurement.
Residual	Difference between the estimated value and the measured value.
Std Residual	Standardised residual, calculated as the residual divided by SD.
Error Model	Uncertainty model applied to a measurement.
Fixed	Error model in which SD is entered directly by the user.
Whiten (PSD)	Error model for size distribution measurements in which SD is calculated automatically from the measured size fraction value. See Whiten (PSD) Model.
Transform	Internal parameter transform used during optimisation. See Transform Options.
Objective	Current fit objective being minimised during the solve. Lower values indicate closer agreement between measured and estimated values.
RMS Std Residual	Root-mean-square value of the standardised residuals.
Max Abs Std Residual	Maximum absolute standardised residual in the current results.
Passes	Continuation or stability passes associated with the current results or solver configuration.
Results out of date	Current displayed results no longer correspond to the current project configuration.
Demo Mode	Unlicensed operating mode in which selected actions and solve sizes are restricted. See Demo Mode.

See Also

• SurveyFit
• SurveyFit (User Guide)
• SurveyFit (Examples)
• Met Dynamics Models overview
• SysCAD Documentation