title: Numpy `ValueError: operands could not be broadcast together with shape ...`
body: <p>Im using python 2.7 and am attempting a forcasting on some random data from 1.00000000 to 3.0000000008. There are approx 196 items in my array and I get the error</p>
  
  <pre><code>ValueError: operands could not be broadcast together with shape (2) (50)
  </code></pre>
  
  <p>I do not seem to be able to resolve this issue on my own.   Any help or links to relevant documentation would be greatly appreciated. </p>
  
  <p>Here is the code I am using that generates this error</p>
  
  <pre><code>nsample = 50
  sig = 0.25
  x1 = np.linspace(0,20, nsample)
  X = np.c_[x1, np.sin(x1), (x1-5)**2, np.ones(nsample)]
  beta = masterAverageList
  y_true = ((X, beta))
  y = y_true + sig * np.random.normal(size=nsample)
  </code></pre>