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

max_context_length must be >= 1, got {max_context_length}

Error message

max_context_length must be >= 1, got {max_context_length}

What it means

Error "max_context_length must be >= 1, got {max_context_length}" thrown in rohitg00/ai-engineering-from-scratch.

Source

Thrown at phases/19-capstone-projects/32-token-positional-embeddings/code/main.py:65

        if ids.dtype != torch.long:
            raise TypeError(f"ids must be long tensor, got {ids.dtype}")
        if ids.dim() != 2:
            raise ValueError(f"ids must be (B, T), got shape {tuple(ids.shape)}")
        return self.embedding(ids)


class LearnedPositionalEmbedding(nn.Module):
    """Position-id to vector lookup with learned parameters."""

    def __init__(
        self,
        max_context_length: int,
        d_model: int,
        init_std: float = DEFAULT_INIT_STD,
    ) -> None:
        super().__init__()
        if max_context_length < 1:
            raise ValueError(f"max_context_length must be >= 1, got {max_context_length}")
        if d_model < 1:
            raise ValueError(f"d_model must be >= 1, got {d_model}")
        self.max_context_length = max_context_length
        self.d_model = d_model
        self.embedding = nn.Embedding(max_context_length, d_model)
        _init_normal(self.embedding.weight, std=init_std)

    def forward(self, seq_len: int) -> torch.Tensor:
        if seq_len < 1:
            raise ValueError(f"seq_len must be >= 1, got {seq_len}")
        if seq_len > self.max_context_length:
            raise ValueError(
                f"seq_len {seq_len} exceeds max_context_length {self.max_context_length}"
            )
        positions = torch.arange(seq_len, device=self.embedding.weight.device)
        return self.embedding(positions)

View on GitHub (pinned to 39ea8a1c6d)

When it happens

Trigger: Thrown at phases/19-capstone-projects/32-token-positional-embeddings/code/main.py:65 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/341342ce76c401fa. Report an issue: GitHub.