Python Reindex Producing Nan : <p>Here is the code that I am working with:</p>

<p><code>import pandas as pd</code></p>

<pre><code>test3 = pd.Series([1,2,3], index = ['a','b','c'])
test3 = test3.reindex(index = ['f','g','z'])
</code></pre>

<p>So originally every thing is fine and test3 has an index of 'a' 'b' 'c' and values 1,2,3. But then when I got to reindex test3 I get that my values 1 2 3 are lost. Why is that? The desired output would be:</p>

<pre><code>f 1
g 2
z 3
</code></pre>
