rohitg00/ai-engineering-from-scratch · error · SystemExit

torch is required for this lesson. Install with: pip install

Error message

torch is required for this lesson. Install with: pip install torch

What it means

Error "torch is required for this lesson. Install with: pip install torch" thrown in rohitg00/ai-engineering-from-scratch.

Source

Thrown at phases/19-capstone-projects/44-cosine-lr-warmup/code/main.py:30

steps on a fixed batch, prints a per-step log, and renders the schedule.
Run: python3 code/main.py
"""

from __future__ import annotations

import csv
import dataclasses
import math
import sys
from dataclasses import dataclass, field
from pathlib import Path
from typing import Callable, Iterable

try:
    import torch
    from torch import nn
except ImportError as exc:
    raise SystemExit(
        "torch is required for this lesson. Install with: pip install torch"
    ) from exc


PLOT_HEIGHT = 12
PLOT_WIDTH = 60


@dataclass
class CosineWithWarmup:
    """Stateless cosine-with-warmup learning-rate schedule.

    Step indexing convention: step zero is the very first training update. At
    step zero the rate is exactly zero (the warmup ramp starts there). At
    step warmup_steps the rate is exactly lr_max. At step total_steps the
    rate is exactly lr_min. Past total_steps the rate stays at lr_min.
    """

View on GitHub (pinned to 39ea8a1c6d)

When it happens

Trigger: Thrown at phases/19-capstone-projects/44-cosine-lr-warmup/code/main.py:30 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of rohitg00/ai-engineering-from-scratch@39ea8a1c6d (2026-08-26). Data as JSON: /api/errors/12e035d11d8bc4e8. Report an issue: GitHub.