qml.gradients.generate_multishifted_tapes¶

generate_multishifted_tapes(tape, indices, shifts, multipliers=None)[source]¶

Generate a list of tapes where multiple marked trainable parameters have been shifted by the provided shift values.

Parameters:

tape (.QuantumTape) – input quantum tape
indices (Sequence[int]) – indices of the trainable parameters to shift
shifts (Sequence[Sequence[float or int]]) – Nested sequence of shift values. The length of the outer Sequence determines how many parameter-shifted tapes are created. The lengths of the inner sequences should match and have the same length as indices.
multipliers (Sequence[Sequence[float or int]]) – Nested sequence of multiplier values of the same format as shifts`. Each multiplier scales the corresponding gate parameter before the shift is applied. If not provided, the parameters will not be scaled.

Returns:

List of quantum tapes. Each tape has the marked parameters: indicated by indices shifted by the values of shifts. The number of tapes will match the summed lengths of all inner sequences in shifts and multipliers (if provided).

Return type:

list[QuantumTape]