title: finding the interpolated intersection between two arrays in Python/Numpy/Scipy
body: <p>I am looking for a simple approach to finding the interpolated intersection between two Numpy arrays. I know that this is simply achieved if we have two function handles, rather than two arrays, as shown in <a href="http://scipy-cookbook.readthedocs.io/items/Intersection.html" rel="nofollow noreferrer">this</a> link using Scipy or using Sympy. I want to do the same, but given two arrays, specifically between the linear spline that results from connecting array entries by lines.</p>
  
  <p>For example, suppose we have two arrays, <code>y_1</code> and <code>y_2</code>, both thyought of as being evaluated at <code>xSupport</code>.</p>
  
  <pre><code>import numpy as np
  xSupport = np.array([0,1])
  y_1 = np.array([0,2])
  y_2 = np.array([1,0])
  </code></pre>
  
  <p>I am looking for the function that returns <code>1/3</code>, which is the x value at the intersections between these two lines. In my application the support is larger than two, so I am looking for an approach that is independent of the arrays' length.</p>