Installation

Prerequisites¶

pylcm requires Python 3.14+. We recommend pixi or uv for environment management.

Install with pixi¶

pixi add pylcm

Install with uv¶

uv add pylcm

Install from GitHub¶

If you require features not yet in a released version, install from GitHub:

# pixi
pixi add pylcm --pypi --git https://github.com/OpenSourceEconomics/pylcm.git --rev main

# uv
uv add pylcm --git https://github.com/OpenSourceEconomics/pylcm.git --rev main

GPU Acceleration (optional, but then this is the whole point of it)¶

pylcm uses JAX for numerical computation. By default, JAX runs on CPU. For GPU acceleration, install the appropriate JAX variant.

Linux (CUDA)¶

If you use pixi, add a CUDA feature to your pyproject.toml:

[tool.pixi.feature.cuda13]
platforms = ["linux-64"]
system-requirements = {cuda = "13"}

[tool.pixi.feature.cuda13.target.linux-64.dependencies]
cuda-nvcc = "~=13.0"

[tool.pixi.feature.cuda13.target.linux-64.pypi-dependencies]
jax = {version = ">=0.8", extras = ["cuda13"]}

For CUDA 12, replace cuda13 with cuda12 throughout.

If you use uv:

uv add "jax[cuda13]"

See the JAX installation guide for details on CUDA toolkit requirements.

macOS (Metal)¶

# pixi
pixi add jax-metal --pypi

# uv
uv add jax-metal

This requires Apple Silicon (M1 or later).

Verify Installation¶

import lcm
import jax

print(jax.devices())  # Should show GPU if configured

If GPU acceleration is set up correctly, you will see a GpuDevice or MetalDevice in the output. Otherwise, you will see CpuDevice, which is fine for development and smaller models.

Troubleshooting¶

• Python version too old: pylcm requires Python 3.14+. Check with python --version.

• JAX GPU not detected: Ensure the CUDA toolkit (Linux) or jax-metal (macOS) is properly installed. See the JAX installation guide.