MultiplyI operation

Warning

This documentation refers to the Classic QDK, which has been replaced by the Modern QDK.

Please see https://aka.ms/qdk.api for the API documentation for the Modern QDK.

Namespace: Microsoft.Quantum.Arithmetic

Package: Microsoft.Quantum.Numerics

Multiply integer xs by integer ys and store the result in result, which must be zero initially.

operation MultiplyI (xs : Microsoft.Quantum.Arithmetic.LittleEndian, ys : Microsoft.Quantum.Arithmetic.LittleEndian, result : Microsoft.Quantum.Arithmetic.LittleEndian) : Unit is Adj + Ctl

Input

xs : LittleEndian

𝑛₁-bit multiplicand

ys : LittleEndian

𝑛₂-bit multiplier

result : LittleEndian

(𝑛₁+𝑛₂)-bit result, must be in state |0⟩ initially.

Output : Unit

Remarks

Uses a standard shift-and-add approach to implement the multiplication. The controlled version was improved by copying out 𝑥ᵢ to an ancilla qubit conditioned on the control qubits, and then controlling the addition on the ancilla qubit.