bitwise_left_shift

→Tensor

bitwise_left_shift(input: Tensor, other: Tensor | Scalar)

source

Element-wise bitwise left shift.

Shifts the bits of input to the left by other positions, filling vacated low-order bits with zero. Equivalent to integer multiplication by $2^{\text{other}}$ modulo the dtype width.

Parameters

inputTensor

Left operand. Must have integer dtype.

otherTensor or scalar

Number of positions to shift. Must be a non-negative integer; shifting by more than the bit-width of input is undefined and clamped or wrapped depending on the underlying integer dtype.

Returns

Tensor

Shifted tensor with shape broadcast(input.shape, other.shape).

Notes

Mathematical definition (modulo the dtype's bit width $W$ ):

\text{out}_i = (\text{input}_i \cdot 2^{\text{other}_i}) \bmod 2^{W}

High-order bits are lost on overflow. Not differentiable.

Examples

>>> import lucid
>>> a = lucid.tensor([1, 2, 4], dtype=lucid.int32)
>>> lucid.bitwise_left_shift(a, 2)
Tensor([4, 8, 16])