Thistle support

Engineering help, without the runaround.

Learn the essentials, solve common problems, and reach the people who build Thistle.

Local calculations No account required No advertising or tracking

Getting started

Your first solution in four steps.

Thistle solves equations simultaneously, so you can describe the system naturally instead of rearranging every expression by hand. It automatically provides initial guesses and, when you choose implicit units, applies units to every variable. If a problem does not converge, review and update the guesses before solving again.

1
Enter equations

Put one equation on each line in the editor.
2
Review variables

Review the guesses, physical bounds, and units for variables.
3
Solve

Choose Solve or press ⌘/Ctrl + Enter.
4
Check the result

Review residuals, units, assumptions, and physical meaning.

Everyday workflow

Keep the basics close.

New project: ⌘/Ctrl + N
Open project: ⌘/Ctrl + O
Save project: ⌘/Ctrl + S
Solve equations: ⌘/Ctrl + Enter

Equation syntax

Write problems the way you think about them.

x + y = 10Equations are solved simultaneously.
T = 300 |K|Units appear between vertical bars.
// noteDouble slashes begin a comment.
T[1] = 300Brackets create indexed variables.

Working examples

Start with something proven.

Copy these patterns into Thistle and adapt the values to your own problem.

Linear system

Solve two equations simultaneously.

x + y = 10
x - y = 2

Units

Attach engineering units directly to values.

P = 101.325 |kPa|
V = 0.5 |m^3|
T = 300 |K|

Thermodynamics

Call built-in fluid-property functions.

P = 100 |kPa|
T = 373.15 |K|
h = h_pt('Water', P, T)

Troubleshooting

When the answer isn’t arriving.

Most solver problems come down to equation balance, units, or a starting point that is too far from the solution.

1Match the number of independent equations to the number of unknowns.
2Check signs, units, property-function arguments, and decimal values.
3Review and update the automatically provided guesses, physical bounds, and variable units.
4Reduce the model to a smaller system to isolate the failing equation.

Frequently asked questions

Good questions, direct answers.

Where does Thistle store my work?

Desktop project files are stored only where you choose to save them. Thistle does not require an account or upload your equations to Praxik.

What should I do when a solution does not converge?

Check that the number of independent equations matches the number of unknowns. Then review units, starting guesses, bounds, and whether the equations describe a physically possible state.

Which file formats does Thistle support?

Use .eqs project files to preserve equations, guesses, bounds, and units. Plain .txt files contain equations only and are useful for import, export, and sharing.

Can I use Thistle results in an engineering design?

Thistle is a computational aid. Important results should be independently checked and reviewed by a qualified professional before they are used for safety, regulatory, or design decisions.

What should I include in a support request?

Include your Thistle version, operating-system version, the steps that reproduce the issue, and the exact error message. You may attach a project file, but remove confidential information first.

Contact support

Tell us what you’re seeing.

Include your Thistle version, operating system, exact error message, and the steps that reproduce the issue. Remove confidential information before attaching a project.

Email info@praxik.com

Developer Praxik, LLC

6701 Corporate Dr Ste N
Johnston, IA 50131
USA