title: How to get Nash-Sutcliffe efficiency by group using hydroGOF package?
body: <p>I am trying to get NSE values grouped by a variable. I tried something similar to:</p>
  
  <pre><code>library(dplyr)
  library(hydroGOF)
  
  mtcars %&gt;% group_by(cyl) %&gt;% 
    NSE(wt,drat)
  </code></pre>
  
  <p>Why isn't it working? It doesn't find "wt". Thank you.</p>