Performing an operation on multiple columns in a list of data
<p>Suppose I have the following data frames in a list:</p>

<pre><code>df1 &lt;- data.frame(x = runif(3), y = runif(3))
df2 &lt;- data.frame(x = runif(3), y = runif(3))
df.list &lt;- list(df1, df2)
</code></pre>

<p>Now suppose I want to add column x and y to get column z
I know to do this in a dataframe with mutate is as easy as:</p>

<pre><code>dplyr::mutate(lapply(df.list, z = x + y))
</code></pre>

<p>How do I perform operations on multiple columns in a list using lapply? </p>