title: Error in colmn vector multiplication ValueError: matmul: Input operand 1 has a mismatch in its core dimension 0
body: <p>I want to multiply a 5x1 matrix with 1x1 matrix in the following way. Every time it is giving the following error</p>
  <pre><code>ValueError: matmul: Input operand 1 has a mismatch in its core dimension 0, with gufunc signature (n?,k),(k,m?)-&gt;(n?,m?)
  </code></pre>
  <p>Here is way I am trying with. Please help me to debug the specific instance here</p>
  <pre><code>&gt;&gt;&gt; m = np.ones(5)
  &gt;&gt;&gt; x = np.ones(1)
  &gt;&gt;&gt; m.shape
  (5,)
  &gt;&gt;&gt; x.shape
  (1,)
  &gt;&gt;&gt; m@x
  Traceback (most recent call last):
    File &quot;&lt;stdin&gt;&quot;, line 1, in &lt;module&gt;
  ValueError: matmul: Input operand 1 has a mismatch in its core dimension 0, with gufunc signature (n?,k),(k,m?)-&gt;(n?,m?) (size 1 is different from 5)
  &gt;&gt;&gt; m.transpose()@x
  Traceback (most recent call last):
    File &quot;&lt;stdin&gt;&quot;, line 1, in &lt;module&gt;
  ValueError: matmul: Input operand 1 has a mismatch in its core dimension 0, with gufunc signature (n?,k),(k,m?)-&gt;(n?,m?) (size 1 is different from 5)
  </code></pre>