title: How to replace certain rows in a dataframe based off of values in another dataframe while preserving order using R?
body: <p>I have a dataframe that looks like this:</p>
  <pre><code>df1 &lt;- data.frame(
    Group = c('A', 'B', 'Total: AB', 'C', 'D', 'Total: CD'),
    Value1 = c(12, 88, 100, 76, 23, 99),
    Value2 = c(10, 82, 92, 71, 21, 92)
  )
  </code></pre>
  <p>And another that looks like this:</p>
  <pre><code>df2 &lt;- data.frame(
    Group = c('A', 'B', 'Total: AB', 'C', 'D', 'Total: CD'),
    Value1 = c(435, 568, 1003, 709, 183, 727),
    Value2 = c(180, 370, 550, 199, 283, 482)
  )
  </code></pre>
  <p>I want to replace the <code>Total</code> rows in <code>df1</code> with their values in <code>df2</code> for a result like this:</p>
  <pre><code>df_desired &lt;- data.frame(
    Group = c('A', 'B', 'Total: AB', 'C', 'D', 'Total: CD'),
    Value1 = c(12, 88, 1003, 76, 23, 727),
    Value2 = c(10, 82, 550, 71, 21, 482)
  )
  </code></pre>
  <p>What's the best way to do this while preserving row order using R, ideally <code>dplyr</code>?</p>