title: gnuplot giving warning: Skipping data file with no valid points
body: <p>I am using the gnuplot script</p>
  
  <pre><code>    #qe.conf
  set terminal png truecolor
  set output "qe.png"
  set xrange ["400" : "700"]
  set yrange ["0" : "1"]
  set style data lines
  plot "qe.txt" using 1:2 title "%Red", '' using 1:3 title "%G-r", '' using 1:4 title "%G-b", '' using 1:5 title "%R"
  </code></pre>
  
  <p>I am executing the gnuplot script qe.conf through a shell script
  It gives me the following error</p>
  
  <blockquote>
    <blockquote>
      <p>gnuplot> plot "qe.txt" using 1:2 title "%Red", '' using 1:3 title "%G-r", '' using 1:4 title "%G-b", '' using 1:5 title "%R"
                                             ^
               line 0: warning: Skipping data file with no valid points</p>
    </blockquote>
    
    <p>gnuplot> plot "qe.txt" using 1:2 title "%Red", '' using 1:3 title
    "%G-r", '' using 1:4 title "%G-b", '' using 1:5 title "%R"
                                                                      ^
             line 0: warning: Skipping data file with no valid points</p>
    
    <p>gnuplot> plot "qe.txt" using 1:2 title "%Red", '' using 1:3 title
    "%G-r", '' using 1:4 title "%G-b", '' using 1:5 title "%R"
                                                                                                 ^
             line 0: warning: Skipping data file with no valid points</p>
    
    <p>gnuplot> plot "qe.txt" using 1:2 title "%Red", '' using 1:3 title
    "%G-r", '' using 1:4 title "%G-b", '' using 1:5 title "%R"
                                                                                                                            ^
             line 0: warning: Skipping data file with no valid points</p>
  </blockquote>
  
  <p>But when I execute qe.conf manually, I works fine</p>
  
  <p>The datafile is here.</p>
  
  <blockquote>
    <p></p>
  </blockquote>
  
  <pre><code>400.0   0.3625060772
  410.0   0.445987595886
  420.0   0.503862994331
  430.0   0.534251869841
  440.0   0.576047041939
  450.0   0.594211326218
  460.0   0.58079588866
  470.0   0.506666961836
  480.0   0.495652452097
  490.0   0.426107864611
  500.0   0.342632041157
  510.0   0.251232093174
  520.0   0.178015786221
  530.0   0.140803848655
  540.0   0.120063881639
  550.0   0.0995420648319
  560.0   0.080193952073
  570.0   0.0730989150532
  580.0   0.0708069989426
  590.0   0.0688014659014
  600.0   0.0597099385221
  610.0   0.0481330987744
  620.0   0.042010859344
  630.0   0.0425115579982
  640.0   0.0460125024438
  650.0   0.0515227545961
  660.0   0.0559745367996
  670.0   0.0629981328342
  680.0   0.0573046109671
  690.0   0.0688715871636
  700.0   0.0742304568215
  </code></pre>
  
  <p>`</p>
  
  <p>Can anyone suggest a solution?</p>
  
  <p>Hi All, After hours of trying I still dont have the answer.
  I tried the following things. I tried giving absolute paths for datafile, gnuscript and shell script. 
  The command gnuplot qe.conf works fine if run from linux command prompt but when run through the shell script gives this error.</p>
  
  <blockquote>
    <p>line 10: warning: Skipping data file with no valid points</p>
  </blockquote>
  
  <p>Request for help.</p>