title: Compact letter display from pairwise test
body: <p>I would like to create a compact letter display from a post-hoc test I did on a linear mixed effect model (lmer)</p>
  
  <p>Here is an example of what I would like when I do a pairwise t.test</p>
  
  <p><code>df &lt;- read.table("https://pastebin.com/raw/Dzfh7b2f", header=T,sep="")</code></p>
  
  <pre><code>library(rcompanion)
  library(multcompView)
  </code></pre>
  
  <pre><code>PT &lt;- pairwise.t.test(df$fit,df$treatment, method=bonferroni)
  PT = PT$p.value
  PT1 = fullPTable(PT)
  multcompLetters(PT1,
                  compare="&lt;",
                  threshold=0.05,
                  Letters=letters,
                  reversed = FALSE)
  </code></pre>
  
  <p><strong>This works our great</strong>, because from the pairwise.t.test, it is easy to simply extract the p values, and create the table I would like.  </p>
  
  <p>Now lets say I run a linear model, do a pairwise comparison, and would like to also create a table, as I did above, that creates a compact letter display for me from the extracted pvalues</p>
  
  <pre><code>
  
  library(multcomp)
  mult&lt;- summary(glht(model, linfct = mcp(treatment = "Tukey")), test = adjusted("holm"))
  mult
  
  </code></pre>
  
  <p>I can see the p values, but have spent the last 2-3 hours trying to figure out how to just extract those values (as I did above with the pairwise.t.test), and subsequently, create a compact letter display table.</p>
  
  <p>Any help is much appreciated. All the best</p>