R and ggplot2 : plot with factors on both axis
<p>My data frame looks like this :</p>

<pre><code>data
&gt;
          | Segment 1 | Segment 2  | Segment 3
Segment 1 | 0.6861964 | 0.16669839 | 0.14710523
Segment 2 | 0.2211293 | 0.69263231 | 0.08623838
Segment 3 | 0.2595055 | 0.05354549 | 0.68694899
</code></pre>

<p>I would like to use in both axis <code>Segment 1</code>, <code>Segment 2</code> and <code>Segment 3</code> and use the values inside the table as parameters to have points of different sizes.</p>

<p>What I tried for the moment is to add a column Segments to the above data frame and did a <code>melt()</code> in order to obtain the following table:</p>

<pre><code>data_melt &lt;- melt(data, id = "Segments")
&gt;
  | Segments  | variable  | value
1 | Segment 1 | Segment 1 | 0.68619638
2 | Segment 2 | Segment 1 | 0.22112931
3 | Segment 3 | Segment 1 | 0.25950552
4 | Segment 1 | Segment 2 | 0.16669839
5 | Segment 2 | Segment 2 | 0.69263231
6 | Segment 3 | Segment 2 | 0.05354549
</code></pre>

<p>Then trying to plot it I am stuck and could not find a ressource solving my problem.</p>

<pre><code>ggplot(test, aes(x = Segments, y = variable, size = value))
    geom_point()
</code></pre>

<p>It plots the axis but no point appears and I get the following message:</p>

<pre><code>geom_point: na.rm = FALSE
stat_identity: na.rm = FALSE
position_identity 
</code></pre>

<p>I would like the output to look like this:
<a href="https://i.stack.imgur.com/CqL7v.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/CqL7v.png" alt="enter image description here"></a></p>