JavaScript interface for writing Quil programs, based on Rigetti Computing's pyQuil package.
Make a list of instructions to run on a hybrid computer with both qubits and classical registers, and then use the measure instruction to store a qubit value onto a classical register.
You can then return the value of these classical registers on each run of your program.
Upgrade to Quantum Quail
Goals: multi-platform, async quantum computing library written in TypeScript
Tests based on the example code in pyQuil
import { gates, inits, operations, Program, QVM, Connection } from 'jsquil'
// request API credentials from http://rigetti.com/forest
let c = new Connection({
user_id: 'USER_ID',
api_key: 'API_KEY'
});
let q = new QVM(c);
let p = new Program();
// put an X gate on the zeroth qubit
p.inst(gates.X(0));
// store the zeroth qubit's value in the first classical register
p.measure(0, 1);
// p now contains Quil instructions, which look like this:
// p.code()
// > X 0
// > MEASURE 0 [1]
// run the program twice, and return the first classical register on each iteration
q.run(p, [1], 2, (err, returns) => {
// err = null
// returns = [[1], [1]]
});
Changing the run command to return three classical registers' values:
q.run(p, [0, 1, 2], 1, (err, returns) => { });
Changing the run command to execute a program ten times:
q.run(p, [0], 10, (err, returns) => { });
Two ways to write a series of gate commands:
p.inst(gates.X(0), gates.Y(1), gates.Z(0));
// same as
p.inst(gates.X(0));
p.inst(gates.Y(1));
p.inst(gates.Z(0));
p.code();
> "X 0\nY 1\nZ 0\n"
p.inst(
gates.H(2),
gates.CPHASE(Math.PI / 2, 1, 2),
gates.H(1),
gates.CPHASE(Math.PI / 4, 0, 2),
gates.CPHASE(Math.PI / 2, 0, 1),
gates.H(0),
gates.SWAP(0, 2)
);
Initializing a classical register value
p.inst( inits.TRUE(0) );
Operations on classical registers
p.inst(operations.EXCHANGE(0, 1));
// others: NOT, AND, OR, MOVE
Reset, wait, and halt commands:
p.reset();
p.wait();
p.halt();
Looping some instructions while a classical register value is TRUE
let classical_register = 2;
let loop_program = new Program();
loop_program.inst(gates.X(0), gates.H(0));
loop_program.measure(0, classical_register);
p.while_do(classical_register, loop_program);
An if-then-else statement combines multiple program objects and chooses one based on a classical register bit value
let then_branch = new Program();
...
let else_branch = new Program();
...
p.if_then(test_register, then_branch, else_branch);
Adding gate and measurement noise to the QVM, to simulate a quantum computer
let gate_noise = [x, y, z];
let measure_noise = [0.2, 0, 0];
let q = new QVM(connection, gate_noise, measure_noise);
If the endpoint changes:
let c = new Connection({
user_id: 'USER_ID',
api_key: 'API_KEY'
}, 'https://endpoint.example.com');
npm install mocha -g
npm test
Apache license (same as pyQuil)