Sim View

Sim View is a lightweight desktop viewer for pulse-sequence simulation outputs from Bruker ParaVision-style simulations and NMRScopeB exports.

It is intended for quick inspection of RF, gradient, and derived channels during pulse-sequence development.

Features

• Load Bruker simulation folders and NMRScopeB output folders
• Inspect RF and gradient channels in a synchronized time view
• Show derived gradient signals such as slew rate, trajectory, and duty cycle
• Export measurements to Excel
• Use either the GUI file picker or launch directly from the command line

Requirements

• Python 3.12 or newer
• A working Qt desktop environment for PyQt6
• poetry for the recommended installation flow

Installation with Poetry

1. Install Python 3.12+ and confirm it is available with python --version
2. Install Poetry from https://python-poetry.org/docs/#installing-with-the-official-installer
3. Install dependencies:

poetry install

4. Start the app:

poetry run python simView.py

Manual Installation

1. Install Python 3.12+
2. Create and activate a virtual environment
3. Install the dependencies listed in pyproject.toml
4. Start the app from that environment:

python simView.py

Usage

• Open the application and choose File -> Open Folder
• Select a simulation output folder containing either Bruker output or NMRScopeB output
• You can also launch the viewer directly for a specific folder:

python simView.py /path/to/simulation_folder

Loading JSON Data Programmatically

from simView import show_graphs_from_dict

import json

path = "/home/vitous/Documents/seqSim/scopeBNew/pulse_seq.json"
with open(path) as f:
    data = json.load(f)

show_graphs_from_dict(data)

ParaVision Integration

For ParaVision integration, use the wrapper script included in this repository.

1. Run ./install_venv.sh to create and populate a project-local .venv
2. Set /path/to/script/run_simview.sh as the viewer command in the ParaVision options menu
3. Wrapper stderr is logged to simview_viewer_errors.log inside the target simulation folder
4. Optional override:

SIMVIEW_ERROR_LOG=/path/to/file /path/to/script/run_simview.sh

AlmaLinux / Qt Notes

• On AlmaLinux, especially over remote connections, Qt may fail to start with an xcb or libxcb-cursor.so.0 error
• Install the missing system package:

sudo dnf install -y xcb-util-cursor

• If needed, also install:

sudo dnf install -y libxkbcommon-x11 mesa-libGL

Testing

Run the full test suite with:

poetry run pytest

If you are using the local virtual environment directly:

.venv/bin/python -m pytest

Current tests cover:

• Core derived-signal logic
• Bruker parser loading against fixture data in testData/mrScanSim

Acknowledgment

If Sim View contributes to your pulse-sequence development or related research, please consider acknowledging the infrastructure support that helped make this work possible:

This work was supported by the core facility ISI-MR within the Czech-BioImaging large RI project (LM2023050), funded by the Ministry of Education, Youth and Sports of the Czech Republic.

We would also be glad to hear about publications, presentations, or internal use cases where the tool proved helpful.

Contact

Questions, feedback, and collaboration notes are welcome at vitous@isibrno.cz.