What is Restart File Creator?

Restart File Creator is a tool that automatically scans RELAP/SCDAPSIM and ASYST output files, identifies all available restart checkpoints with their simulation times, and generates clean, formatted restart input decks. It eliminates manual parsing, validates the deck before writing it, and allows you to resume interrupted simulations exactly where they left off.

Why do I need Restart File Creator?

Restart File Creator saves hours of computational time by allowing you to recover from interruptions (power outages, system maintenance), explore alternative scenarios from stable baselines without repeating computations, debug with precision by restarting from specific time points, and accelerate parametric studies from established baselines.

What file formats does Restart File Creator use?

Restart File Creator reads RELAP/SCDAPSIM and ASYST output files (.o) to find the available checkpoints, and the matching input deck (.i) to pick up the required run type card. It generates a formatted restart input deck. Restart points are commented out by default for safety, and one click makes the checkpoint you want the active one.

What platforms does Restart File Creator support?

Restart File Creator is available as a standalone executable for Windows 10+ and macOS 10.13+, with no installation or dependency management required. A Linux version is coming soon.

Will Restart File Creator overwrite my binary restart file?

No. RELAP/SCDAPSIM and ASYST write binary restart and plot data to a .r file, and that is the file a restart depends on. Restart File Creator proposes an output name that cannot collide with it, and refuses outright to write over a binary file whatever name you give it. Existing text files are confirmed before they are replaced.

Does Restart File Creator check that the restart deck will run?

Yes. Two checks run before the file is written. It confirms the required 100 restart card is present, since without it the deck will not run, and it confirms exactly one restart point is active. None means the file restarts nothing, and two or more is invalid, so the tool reports the problem rather than writing a deck that would be rejected.

How much does Restart File Creator cost?

Restart File Creator is available for a one-time purchase of $29.99 with a perpetual license and lifetime updates. A bundle with Strip File Creator is available for $49.99, providing significant savings.

Restart File Creator

Save Time. Resume Work. Accelerate Discovery.

Restarting complex ASYST or RELAP/SCDAPSIM simulations no longer needs to be manual or error-prone. Restart File Creator automatically scans output files, identifies all available restart checkpoints, and generates clean, formatted restart input files for immediate use.

Instant Recovery

Resume interrupted simulations exactly where they left off after power outages or system maintenance.

Efficient Exploration

Start from stable baselines to investigate different configurations without repeating computations.

Precise Debugging

Pinpoint problematic behavior by restarting from specific time points to isolate issues faster.

Why Restart File Creator?

Your engineering time is too valuable to waste on repeated computations

Recover from Interruptions Instantly

System maintenance? Power outage? Hardware upgrade? Don't lose days of computational work. Resume your long-running thermal-hydraulic simulations exactly where they left off.

Explore Alternative Scenarios Efficiently

Starting from a stable simulation state, investigate different system configurations, parameter variations, or operational conditions without repeating baseline computations.

Debug with Precision

Pinpoint problematic behavior by restarting simulations from specific time points. Isolate issues faster and iterate on solutions more efficiently.

Accelerate Parametric Studies

Generate multiple restart points to conduct time-series analysis or parametric investigations from established baselines—ideal for comprehensive system characterization.

Powerful Capabilities

Everything you need to manage simulation restarts with confidence

Intelligent Checkpoint Detection

Automatically scans your RELAP/SCDAPSIM and ASYST output files to identify all available restart points with corresponding timestamps. No manual parsing required.

Scans output files automatically
Lists every checkpoint with its simulation time
Sort by restart number or time, and filter to the window you care about
Compatible with both RELAP/SCDAPSIM and ASYST

Flexible Selection Options

Choose single checkpoints, select ranges, or list them all — then make the one you want active with a single click. No hunting for a line to uncomment.

Single checkpoint selection
Range selection for multiple points
Generate files with all restart points
Use This One sets the active checkpoint and names the file to match

Safety-First Design

Restart points are commented out by default, and the deck is checked before it is written — so the two things that most often break a restart are caught first.

Never overwrites your binary restart file — the one file you cannot regenerate
Confirms the required 100 restart card is present
Confirms exactly one restart point is active — never none, never two
Existing files are confirmed before they are replaced

Smart File Management

Intelligent filename generation incorporates restart point numbers for easy organization. Custom title lines help you document your simulation series.

Automatic filename generation
Custom title lines for documentation
Preview before generating, with full undo and redo
Freely editable content — your edits are kept when checkpoints change

Built for Engineers

Designed with your workflow in mind

No Installation Hassles

Standalone executable requires no Python or dependency management

Cross-Platform Ready

Works seamlessly on Windows 10+ and macOS 10.13+

Clean Interface

Purpose-built GUI eliminates complexity and confusion

Built-in Help

Comprehensive documentation ensures you're never stuck

Ideal For

Continuing Interrupted Simulations

Resume work after unexpected interruptions without starting over

Parametric Studies

Start from stable baselines for efficient parameter exploration

Debugging Safety Analysis Runs

Isolate and fix issues faster with targeted restarts

Accelerating Computational Workflows

Save hours of computational time on every project

Technical Specifications

Professional-grade tool built for reliability

Input Format

RELAP/SCDAPSIM and ASYST output files (.o), plus the matching input deck (.i), which supplies the required run type card

Output Format

A formatted restart input deck, named after the checkpoint you selected

Validation

Card 100 present, exactly one restart point active, and binary restart files protected from being overwritten

Platform

Windows 10+, macOS 10.13+

Deployment

Standalone executable with bundled dependencies

Transform Your Workflow

Restart File Creator puts checkpoint management at your fingertips

Current Version

1.0

Compatible with RELAP/SCDAPSIM and ASYST simulation outputs

Linux version coming soon

💰 Special Offer

Bundle & Save!

Get both Strip File Creator and Restart File Creator together

Strip File Creator

$29.99

+

Restart File Creator

$29.99

Regular Price: $59.98

Bundle Price: $49.99

Save $9.99!

Perpetual License • Lifetime Updates

See all products in the store

Ready to Save Hours of Computational Time?

Get Restart File Creator today and resume your simulations with confidence.

$29.99

One-time purchase • Lifetime access

Browse All Products Learn More

Questions about integration? Contact our support team

References & Resources

Restart File Creator works with RELAP5/SCDAPSIM simulation checkpoints used in nuclear safety analysis regulated by the U.S. Nuclear Regulatory Commission (NRC). The underlying simulation codes were originally developed at Idaho National Laboratory (INL).