title: Pandas Select Rows Start to End with Specific Starting Value in Column
body: <p>this is something simple but I have not found an answer. I have a dataframe 'df1' that looks like this:</p>
  <pre><code>    year      5
  0   1948 -99.99
  1   1949 -99.99
  2   1950  -1.74
  3   1951   0.17
  4   1952  -0.93
  </code></pre>
  <p>And, I simply need to select rows beginning with the 'year' column == 1950 and then to the end of the rows (which in this case is '1952').</p>
  <p>I have tried this below but I just get &quot;False&quot;, &quot;True&quot; but I just get a &quot;True&quot; when 'yearstart' = 1950. So, if 'yearstart' == 1950, i get the following. I'm not sure how to execute a yearstart and extract all the data to the end of the rows.</p>
  <pre><code>yearstart = 1950
  
  df2 = [df1.year==yearstart]
  </code></pre>
  <p>I get this -</p>
  <pre><code>[0     False
   1     False
   2      True
   3     False
   4     False
  </code></pre>
  <p>What I need is this:</p>
  <pre><code>df2 = 
  
      year      5
  0   1950  -1.74
  1   1951   0.17
  2   1952  -0.93
  </code></pre>