{"record":{"id":"3dd8c7f6cd31f44c","repo":"rohitg00/ai-engineering-from-scratch","slug":"expected-b-l-ids-got-tuple-ids-shape","errorCode":null,"errorMessage":"expected (B, L) ids, got {tuple(ids.shape)}","messagePattern":"expected \\(B, L\\) ids, got (.+?)","errorType":"validation","errorClass":"ValueError","httpStatus":null,"severity":"error","filePath":"phases/19-capstone-projects/60-projection-layer-modality-align/code/main.py","lineNumber":90,"sourceCode":"\nclass MockTextEmbedding(nn.Module):\n    \"\"\"Frozen text table used as alignment targets.\n\n    Captions are sequences of token ids; the caption embedding is the mean of\n    the embedded ids. Deterministic given seed.\n    \"\"\"\n\n    def __init__(self, vocab_size: int, dim: int, seed: int) -> None:\n        super().__init__()\n        gen = torch.Generator().manual_seed(seed)\n        weight = torch.randn(vocab_size, dim, generator=gen) * (1.0 / dim ** 0.5)\n        self.table = nn.Embedding(vocab_size, dim, _weight=weight)\n        for p in self.table.parameters():\n            p.requires_grad_(False)\n\n    def forward(self, ids: torch.Tensor) -> torch.Tensor:\n        if ids.dim() != 2:\n            raise ValueError(f\"expected (B, L) ids, got {tuple(ids.shape)}\")\n        embed = self.table(ids)\n        mask = (ids != 0).float().unsqueeze(-1)\n        denom = mask.sum(dim=1).clamp(min=1.0)\n        pooled = (embed * mask).sum(dim=1) / denom\n        return pooled\n\n\ndef make_pair(seed: int, vocab_size: int, max_len: int) -> tuple[torch.Tensor, torch.Tensor]:\n    \"\"\"One synthetic (image, caption_ids) pair.\n\n    Image is the deterministic 224x224x3 fixture from lesson 58 with a per-pair\n    seed. Caption is a length-`max_len` sequence of token ids, again\n    deterministic in seed. Token id 0 is reserved as padding.\n    \"\"\"\n    img = synthesize_image(seed=seed)\n    rng = np.random.default_rng(seed + 10_000)\n    length = int(rng.integers(4, max_len + 1))\n    ids = np.zeros((max_len,), dtype=np.int64)","sourceCodeStart":72,"sourceCodeEnd":108,"githubUrl":"https://github.com/rohitg00/ai-engineering-from-scratch/blob/39ea8a1c6d0b61f071226eff7ede4d4105fed820/phases/19-capstone-projects/60-projection-layer-modality-align/code/main.py#L72-L108","documentation":"Error \"expected (B, L) ids, got {tuple(ids.shape)}\" thrown in rohitg00/ai-engineering-from-scratch.","triggerScenarios":"Thrown at phases/19-capstone-projects/60-projection-layer-modality-align/code/main.py:90 when the library encounters an invalid state.","commonSituations":"See trigger scenarios.","solutions":[],"exampleFix":null,"handlingStrategy":null,"validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"39ea8a1c6d0b61f071226eff7ede4d4105fed820","analyzedAt":"2026-08-26T03:13:46.626Z","schemaVersion":2},"datasetVersion":"2026-08-26T07:17:17.940Z"}