GCI Calculator GUI

A cross-platform Qt-based graphical user interface for calculating the Grid Convergence Index (GCI), based on the procedure presented by Celik et al. (2008).

This application calculates:

• Grid refinement ratios ($r_{21}, r_{32}$)
• Apparent order of the method ($p$)
• Extrapolated values ($\phi_{ext}$)
• Approximate and extrapolated relative errors
• Fine grid convergence index ($GCI^{21}$)

Download & Installation

You do not need to compile the application yourself. Pre-compiled binaries for Linux, Windows, and macOS are automatically generated for every release.

1. Go to the Releases page of this repository.
2. Download the appropriate file for your operating system:

Windows

Download the .exe file. It is a standalone portable executable.

Linux

Download the .AppImage file.

chmod +x GciGui-x86_64.AppImage
./GciGui-x86_64.AppImage

macOS (Intel & Apple Silicon)

Download the macOS .zip file and extract GciGui.app.

Note on macOS Security: Because this is an open-source tool and not signed with a paid Apple Developer certificate, macOS Gatekeeper will flag it as an "unidentified developer." To run it, right-click the app and select Open, or clear the quarantine flag via terminal:

xattr -cr /path/to/GciGui.app

Usage

1. Input Grid Data:
   • Fine Grid: Enter the representative cell size ($h_1$) and the parameter of interest ($\phi_1$).
   • Medium Grid: Enter $h_2$ and $\phi_2$.
   • Coarse Grid: Enter $h_3$ and $\phi_3$.
2. Calculate: Click the "Run GCI Analysis" button.
3. Results: View the computed GCI, Apparent Order, and related parameters in the results pane. Detailed calculation warnings will appear in the log window.

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Building Locally (For Developers)

If you wish to compile the application from source, you will need CMake (3.16+), a C++17 Compiler, and the Qt 6 SDK.

Linux

sudo apt-get update && sudo apt-get install build-essential cmake qt6-base-dev
cmake -B build -DCMAKE_BUILD_TYPE=Release
cmake --build build
./build/GciGui

macOS (via Homebrew)

brew install cmake qt@6
cmake -B build -DCMAKE_BUILD_TYPE=Release -DCMAKE_PREFIX_PATH=$(brew --prefix qt@6)
cmake --build build
macdeployqt build/GciGui.app

Releasing a New Version

The CI/CD pipeline uses GitHub Actions to automatically build and package the .exe, .AppImage, and .app bundle whenever a new tag is pushed.

git tag v1.0.0
git push origin v1.0.0

License

This project is licensed under the GNU General Public License v3.0 (GPLv3) - see the LICENSE file for details.