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torch.IndexSpec

export type IndexSpec = number | RangeSpec | null | '...' | MaskSpec | IndicesSpec;

Values

number
RangeSpec
null
'...'
MaskSpec
IndicesSpec

Index specification for a single dimension in .at() calls.

number: Select single index (removes dimension, like Python's x[i])
[start, end]: Slice range (like Python's x[start:end])
[start, end, step]: Strided slice (like Python's x[start:end:step])
null: Keep entire dimension (like Python's x[:])
'...': Ellipsis - expands to fill remaining dimensions (like Python's x[...])
Tensor (boolean): Masked selection - returns 1D tensor (like Python's x[mask])
Tensor (integer): Index selection along dimension (like Python's x[indices])

Examples

// Python equivalents:
// x[0]        → 0
// x[1:5]      → [1, 5]
// x[::2]      → [0, null, 2]  (every other element)
// x[1:10:2]   → [1, 10, 2]
// x[:]        → null
// x[..., 0]   → '...', 0
// x[mask]     → mask (boolean Tensor)
// x[indices]  → indices (integer Tensor)

IndexSelectShape