title: ggplot and barchart with multiple variable in an certain order
body: <p>I´ve working for days on this problem but i am not able to solve this problem.
  I have a matrix </p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
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  <pre class="snippet-code-html lang-html prettyprint-override"><code>gesamt
       year &lt;10 10-60 60-100 100-150 &gt;150
  2001 2001 376    57      7       0    0
  2002 2015 322    60     10       2    0
  2003 2016 324    59      5       2    0</code></pre>
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  <p>which i convert to data.frame: <strong>df &lt;- data.frame(gesamt)</strong></p>
  
  <p>and melt it: </p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
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  <pre class="snippet-code-html lang-html prettyprint-override"><code>df.molten &lt;- melt(df, id.vars='year', value.name='mean')
  
  df.molten
     year variable mean
  1  2001      &lt;10  376
  2  2015      &lt;10  322
  3  2016      &lt;10  324
  4  2001    10-60   57
  5  2015    10-60   60
  6  2016    10-60   59
  7  2001   60-100    7
  8  2015   60-100   10
  9  2016   60-100    5
  10 2001  100-150    0
  11 2015  100-150    2
  12 2016  100-150    2
  13 2001     &gt;150    0
  14 2015     &gt;150    0
  15 2016     &gt;150    0</code></pre>
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  <p>I would like to get a solution like this:</p>
  
  <p><a href="https://i.stack.imgur.com/QloUy.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/QloUy.jpg" alt="enter image description here"></a></p>
  
  <p>But i am not able to plot it (didn´t had enough time to study ggplot2), whatever i tried. </p>
  
  <p>Any hints?</p>