title: How to remove palette colors heatmap
body: <p>Is possible if heatmap palette(small rectangle on the right) to be removed? </p>
  
  <p>this is my data</p>
  
  <pre><code>    a       b       c   
  1   181 80  121 10  34 20
  2   18 20   17 20   13 20
  3   12 20   5 30    20 20
  </code></pre>
  
  <p>this is my gnuplot script</p>
  
  <pre><code>set term pos eps font 20
  unset key
  set nocbtics
  set palette rgbformulae -7, 2, -7
  set title "Faults"
  
  set size 1, 0.5
  set output 'heatmap2.eps'
  YTICS="`awk 'BEGIN{getline}{printf "%s ",$1}' 'data2.dat'`"
  XTICS="`head -1 'data2.dat'`"
  set for [i=1:words(XTICS)] xtics ( word(XTICS,i) i-1 )
  set for [i=1:words(YTICS)] ytics ( word(YTICS,i) i-1 )
  
  set for [i=1:words(XTICS)] xtics ( word(XTICS,i) 2*i-1 )
  plot "&lt;awk '{$1=\"\"}1' 'data2.dat' | sed '1 d'" matrix every 2::1 w image, \
       '' matrix using ($1+1):2:(sprintf('%d', $3)) every 2 with labels
  </code></pre>
  
  <p>I want to remove the palette because I adjust the ploting colors by percentage of my data. So, I guess the palette on the right my table is now use anymore. Thanks</p>