title: Finding the index inside a vector satisfying a condition
body: <p>I am looking for a condition which will return the index of a vector satisfying a condition.</p>
  
  <p>For example-
  I have a vector <code>b = c(0.1, 0.2, 0.7, 0.9)</code>
  I want to know the first index of b for which say b >0.65. In this case the answer should be 3</p>
  
  <p>I tried <code>which.min(subset(b, b &gt; 0.65))</code>
  But this gives me 1 instead of 3.</p>
  
  <p>Please help</p>