title: In R, how to get powers of ten in bold font in a plot label?
body: <p>I want to have "10^4 points" in bold as my x-axis label.</p>
  
  <p>I know how to make a simple label in bold:</p>
  
  <pre><code>plot(1:10, xlab="")
  mtext(text="10 points", side=1, font=2, line=3)
  </code></pre>
  
  <p>Thanks to <a href="https://stackoverflow.com/a/10216832/597069">this answer</a>, I know how to make a label with a power of ten but nothing is in bold:</p>
  
  <pre><code>mtext(text=expression(paste(10^4, " points")), side=1, font=2, line=3)
  </code></pre>
  
  <p>Thanks to <a href="https://stackoverflow.com/a/6047422/597069">this answer</a>, I also know how to make a label with a Greek letter in bold:</p>
  
  <pre><code>mtext(text=expression(bold(paste(beta, "=", 10^1, " points"))), side=1, line=3)
  </code></pre>
  
  <p>But still the power of ten is not in bold!</p>
  
  <p>It doesn't work either with <code>bquote</code>:</p>
  
  <pre><code>mtext(text=bquote(bold(10^1~points)), side=1, line=3)
  </code></pre>
  
  <p>Any idea?</p>
  
  <p>Here are some details about my system. Let me know if you need anything else.</p>
  
  <pre><code>&gt; sessionInfo()
  R version 2.15.0 (2012-03-30)
  Platform: x86_64-redhat-linux-gnu (64-bit)
  
  locale:
   [1] LC_CTYPE=en_US.UTF-8       LC_NUMERIC=C              
   [3] LC_TIME=en_US.UTF-8        LC_COLLATE=en_US.UTF-8    
   [5] LC_MONETARY=en_US.UTF-8    LC_MESSAGES=en_US.UTF-8   
   [7] LC_PAPER=C                 LC_NAME=C                 
   [9] LC_ADDRESS=C               LC_TELEPHONE=C            
  [11] LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C       
  
  attached base packages:
  [1] stats     graphics  grDevices utils     datasets  methods   base     
  </code></pre>