def getG(i):
    if SG[i] == n1:
        return omega1
    elif SG[i] == n2:
        return omega2

def getq(i, j):
    if g == i + 1:
        return getG(i)
    elif g == i - t - 1:
        return getG(t-1)
    else:
        return 0

In [112]: [[getq(i, g) for g in range(0, t)] for i in range(0, t)]
Out[112]:
[[0, (-0.68454710592868873+0.65607176467927031j), 0],
 [0, 0, (-0.68454710592868873+0.65607176467927031j)],
 [0, 0, 0]]
In [113]: [[(i, g) for g in range(0, t)] for i in range(0, t)]
Out[113]: [[(0, 0), (0, 1), (0, 2)], [(1, 0), (1, 1), (1, 2)], [(2, 0), (2, 1), (2, 2)]]
In [114]: getq(0, 0)
Out[114]: 0

In [115]: getq(0, 1)
Out[115]: 0

In [116]: getq(0, 2)
Out[116]: 0

In [117]: getq(1, 0)
Out[117]: (-0.68454710592868873+0.65607176467927031j)

In [118]: getq(1, 1)
Out[118]: (-0.68454710592868873+0.65607176467927031j)

In [119]: getq(1, 2)
Out[119]: (-0.68454710592868873+0.65607176467927031j)

In [120]: getq(2, 0)
Out[120]: 0

In [121]: getq(2, 1)
Out[121]: 0

In [122]: getq(2, 2)
Out[122]: 0