title: overflow in exp(x) in python
body: <p>I'm using function: numpy.log(1+numpy.exp(z))</p>
  
  <p>for small values of z (1-705) it gives identity result(1-705 {as expected}), 
  but for larger value of z from 710+ it gives infinity, and throw error "runtimeWarning: overflow encountered in exp"</p>