title: Finding index of maximum value in array with NumPy
body: <p>I would like to find a maximum in a <code>float64</code> array, excluding <code>nan</code> values.</p>
  
  <p>I saw <code>np.nanmax</code> function but it doesn't give the index corresponding to the found value.</p>
  
  <p>it 's quite strange to scan after to the value specially the function necessarily use the index ??? Can't it be a mistake searching like that . </p>
  
  <p>isn't there a way to recover the index directly ?</p>