Double pendulum · deepseek-v3.2-exp
Simulate a chaotic double pendulum on a canvas using the correct equations of motion, drawing the arms and a colorful fading trail of the tip.
transcript · 6 messages
Simulate a chaotic double pendulum on a canvas using the correct equations of motion, drawing the arms and a colorful fading trail of the tip.
thinking
I'll create a single-page web app that simulates a chaotic double pendulum with proper physics, arms, and a colorful fading trail. I'll write it all into index.html. First, let's check the current directory.
{"command":"pwd && ls -la"}/tmp/ws total 0 drwxr-sr-x. 2 node node 6 Aug 1 19:52 . drwxrwsrwx. 3 root node 16 Aug 1 19:52 ..
thinking
Now I'll write the index.html file. I'll include a canvas, style it, and write JavaScript that simulates the double pendulum using Lagrangian mechanics. I'll implement Runge-Kutta integration for accuracy, and draw the pendulum arms with a trail that fades with a gradient. Let's create the file.
index.html (24891 bytes)Successfully wrote 24891 bytes to index.html
I've created a complete, self-contained single-page web app that simulates a chaotic double pendulum with the correct equations of motion. The app includes: **Key Features:** 1. **Physics Simulation**: Uses Lagrangian mechanics to derive the equations of motion for a double pendulum, integrated with 4th-order Runge-Kutta method for accuracy 2. **Visual Elements**: - Two pendulum arms with adjustable masses shown as proportional circles - Colorful fading trail of the second pendulum's tip with hue cycling - Gradient background for visual appeal - Real-time energy calculations (kinetic, potential, total) **Interactive Controls:** - Adjustable masses (0.5-5 kg) - Adjustable arm lengths (0.5-3 m) - Adjustable gravity (1-20 m/s²) - Trail length control (100-2000 points) - Reset, Pause/Resume, and Randomize buttons **Physics Display:** - Real-time angles and angular velocities - Energy calculations (kinetic, potential, total) - Simulation time - Frame rate counter **Technical Details:** - All code is contained in one `index.html` file (CSS in `<style>`, JavaScript in `<script>`) - No external dependencies or network requests - Responsive design that works on mobile and desktop - High DPI display support - Smooth animation with requestAnimationFrame The double pendulum exhibits chaotic behavior - small changes in initial conditions lead to drastically different trajectories, which is clearly visible in the colorful trail. The simulation uses real physics equations and provides an educational yet visually engaging experience.
TAKE IT TO CODE
A single self-contained HTML file — copy it and open in any browser, or reuse the prompt with your own pi-agent run.
RUN
EVALUATION
Double pendulum simulation runs continuously with colorful fading trails and live physics stats; keyboard inputs just correspond to time progression, not distinct controls.
Vision grade · anthropic/claude-sonnet-5
MEASUREMENTS
Raw readings from the capture, not a verdict — the grade above is the only judgement. Percentages are how much of the screen changed; the measure under-reports sparse motion on a dark background.