</span> error in evaluating the argument 'x' in selecting a method for function 'plot': values must be type 'double',</span>
<span class="r-err co"><span class="r-pr">#&gt;</span>  but FUN(X[[1]]) result is type 'character'</span>
<span class="r-plt img"><img src="ladderize-1.png" alt="" width="700" height="433"></span>
</code></pre></div>
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