title: How to plot a graph with linux?
body: <p>I want to plot a data file (<code>speed11.data</code>) in Linux. 
  the data file looking like:</p>
  
  <pre><code>1,4.45823517e+01
  2,4.45873528e+01
  3,4.45923538e+01
  4,4.45973549e+01
  </code></pre>
  
  <p>I used gnuplot, but I got error.</p>
  
  <pre><code> gnuplot&gt; plot "speed11.data"
  
  
  gnuplot&gt; 1,4.45823517e+01
           ^
           "speed11.data", line 1: invalid command
  </code></pre>
  
  <p>How to plot this graph?</p>
  
  <p>The output of <code>locale</code> is:</p>
  
  <pre><code>LANG=en_CA.UTF-8
  LC_CTYPE="en_CA.UTF-8"
  LC_NUMERIC="en_CA.UTF-8"
  LC_TIME="en_CA.UTF-8"
  LC_COLLATE="en_CA.UTF-8"
  LC_MONETARY="en_CA.UTF-8"
  LC_MESSAGES="en_CA.UTF-8"
  LC_PAPER="en_CA.UTF-8"
  LC_NAME="en_CA.UTF-8"
  LC_ADDRESS="en_CA.UTF-8"
  LC_TELEPHONE="en_CA.UTF-8"
  LC_MEASUREMENT="en_CA.UTF-8"
  LC_IDENTIFICATION="en_CA.UTF-8"
  LC_ALL=
  </code></pre>