title: how do I find the average of this array but only for the values that are not equal to zero in python
body: <p>array([1500, 1520, 1540, 1590, 1590, 1600, 1600, 1560, 1560, 1560, 1580,
  1520, 1460, 1510, 1520, 1320, 1320, 1300, 1300, 1320, 1320, 1320,
  1320, 1300, 1300, 1340, 1300, 1300, 1300, 1400, 1480, 1360, 1420,
  1480, 1580, 1530, 1500, 1480, 1480, 1480, 1460, 1540, 1490, 1480,
  1480, 1520, 1500, 1460, 1480, 1480, 1500, 1500, 1600, 1540, 1480,
  1460, 1560, 1600, 1560, 1600, 1600, 1600, 1620, 1600, 1580, 1600,
  1700, 1620, 1620, 1620, 1700, 1700, 1680, 1640, 1620, 1670,    0,
  0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
  0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
  0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
  0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
  0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
  0,    0,    0,    0,    0,    0,    0,    0,    0,    0, 1670,
  0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
  0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
  0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
  0,    0,    0,    0,    0, 1600, 1680,    0,    0,    0,    0,
  0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
  0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
  0,    0,    0], dtype=int64)</p>