keras-team/keras · error · ValueError

Cannot convert '{shape}' to a shape. Negative dimensions are

Error message

Cannot convert '{shape}' to a shape. Negative dimensions are not allowed.

What it means

Error "Cannot convert '{shape}' to a shape. Negative dimensions are not allowed." thrown in keras-team/keras.

Source

Thrown at keras/src/backend/common/variables.py:641

            continue

        # Reject these even if they can be cast to int successfully.
        if isinstance(d, (str, float)):
            raise ValueError(
                f"Cannot convert '{shape}' to a shape. "
                f"Found invalid dimension '{d}' of type '{type(d)}'. "
            )

        try:
            # Cast numpy scalars, tf constant tensors, etc.
            d = int(d)
        except Exception as e:
            raise ValueError(
                f"Cannot convert '{shape}' to a shape. "
                f"Found invalid dimension '{d}' of type '{type(d)}'. "
            ) from e
        if d < 0:
            raise ValueError(
                f"Cannot convert '{shape}' to a shape. "
                "Negative dimensions are not allowed."
            )
        standardized_shape.append(d)

    # This also turns subclasses of `tuple` (e.g. `torch.Size`) to plain tuple.
    return tuple(standardized_shape)


def shape_equal(a_shape, b_shape):
    """Return whether a_shape == b_shape (allows None entries)."""
    if len(a_shape) != len(b_shape):
        return False
    for e1, e2 in zip(a_shape, b_shape):
        if e1 is not None and e2 is not None and e1 != e2:
            return False
    return True

View on GitHub (pinned to 7a34a03db6)

When it happens

Trigger: Thrown at keras/src/backend/common/variables.py:641 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of keras-team/keras@7a34a03db6 (2026-08-25). Data as JSON: /api/errors/b0717a6812348683. Report an issue: GitHub.