How can I compose a list of quantum circuits onto different qubits in one command?

Question

This is a follow-up question on composing the quantum circuits. Say if I have the following circuit element:

def qc1(a):                      
    quanc1 = QuantumCircuit(2)
    quanc1.x(0)
    quanc1.h(1)
    quanc1.crz(a,1,0)
    quanc1.barrier()
    return quanc1

and circ is a list that contains multiple elements:

circ = []
for i in range (3):
    circ.append(qc1(np.pi+i))

Then using the reduce function, I could combine those 3 circuits and compose them into a larger quantum circuit:

from functools import reduce
qc = QuantumCircuit(5,5)
qc = reduce(lambda x,y: x.compose(y,[2,4]),circ, qc)

The code works to compose the circuits in circ onto qubit 2 and 4 of qc:

However, if I have another set of coordinates:

c = [[2,1],[2,4],[2,3]]

Is it possible for me to compose the circuits in circ onto those pairs of coordinates, separately (instead of the fixed pair [2,4])? Or is there a simpler method than using reduce? Thanks!

Answer 1

We could use the zip function twice:

A = [...]
B = [...]
qc = reduce(lambda x,y: x.compose(y[0],[y[1][0],y[1][1]]),zip(circ,zip(A,B)), qc)

Where A and B are two lists that contain the information about which qubits we want to compose:)