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Quickstart File

Author: ericgol

NEXT_Quickstart_Under_30_Seconds.md

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+# ⚡ Run a NEXT Simulation in Under 30 Seconds
+
+This quickstart shows how to build and run a minimal simulation using the **NEXT (Newtonian EXact Trajectories)** codebase in under 30 seconds on a typical developer machine.
+
+---
+
+## Prerequisites
+
+- Git
+- CMake (≥ 3.10)
+- C++ compiler (Clang, GCC, or MSVC)
+- Python 3 (for example input generation)
+
+---
+
+## 🚀 Quickstart
+
+### 1. Clone the repository
+
+```bash
+git clone https://github.com/TimGoTheCreator/NEXT.git
+cd NEXT
+```
+
+---
+
+### 2. Build the simulator
+
+```bash
+mkdir build
+cd build
+cmake ..
+cmake --build . --config Release
+cd ..
+```
+
+This produces the `next` executable in the build directory.
+
+---
+
+### 3. Run a built-in example simulation
+
+```bash
+cd examples/TwoBodies
+python two_body.py
+../../build/next two_body.txt 8 0.01 0.1 vtu
+```
+
+**Arguments explained:**
+
+- `two_body.txt` – input file generated by the Python script  
+- `8` – number of CPU threads  
+- `0.01` – time step  
+- `0.1` – total simulation time  
+- `vtu` – output format (VTK Unstructured Grid)
+
+---
+
+### 4. View the results
+
+The simulation outputs a `.vtu` file in the example directory.
+
+To visualize:
+- Open the file in **ParaView**
+- Load the dataset and press *Play* to view particle trajectories
+
+---
+
+## 🧠 What This Demonstrates
+
+- Successful compilation of the NEXT C++ engine
+- Generation of initial conditions via Python
+- Execution of an N-body simulation
+- Export of results to a standard visualization format
+
+This workflow is intended as the fastest possible validation that NEXT builds and runs correctly.
+
+---
+
+## Notes
+
+- Build times may vary depending on compiler and system.
+- For longer or higher-resolution simulations, adjust thread count, timestep, and total time accordingly.
+- Additional examples are available under the `examples/` directory.
+
+---
+
+✅ **Expected total time**: ~20–30 seconds on a modern development machine.