# Example 10 -- Draw color image plot # Test various colorscales. # INSTRUCTIONS: Uncomment one of the following '\scale = ' statements # CASE 1: From black at high values to white at low values #\scale = "rgb 0 0 0 20.0 rgb 1 1 1 0.0 increment 5" # CASE 2: From skyblue at 20 to tan for 0; traverse RGB space # See also case 5, which names the colors. #\scale = "rgb 0.529 0.808 0.922 20.0 rgb 0.824 0.706 0.549 0.0 increment 5" # CASE 3: From skyblue at 20 to tan for 0; traverse HSB space # Is it just me, or is this uglier than case 2? #\scale = "hsb 0.548 0.426 0.922 20.0 hsb 0.095 0.334 0.824 0.0 increment 5" # CASE 4: Use a spectrum; traverse HSB space #\scale = "hsb 0 1 1 20.0 hsb 0.6666 1 1 0.0 increment 5" # CASE 5: From skyblue to tan, traversing RGB space (by default) # (Compare case 2, which uses similar endpoints, with # colors specified with RGB values, and larger increment.) #\scale = "skyblue 20.0 tan 0.0 increment 2" # CASE 6: From skyblue to tan, traversing RGB space (by default) # Compare 2 and 5; note this has continuous increment #\scale = "skyblue 20.0 tan 0.0" # CASE 7: From blue to brown \scale = "blue 20.0 brown 0.0 increment 2.5" open example10.dat read line \header read \D read .nx. read .ny. set x name "distance along cove" set y name "time" set x grid 0 1 /.nx. set x axis 0 1 0.5 0.1 set y grid 0 .ny. / .ny. set y axis 0 .ny. read grid data * * .ny. .nx. set image range 0 20 convert grid to image set image colorscale \scale draw image # Draw contours in white ink set graylevel 1.0 draw contour 0 20 1 unlabelled set graylevel 0.0 draw axes # redraw in case whited out draw image palette left -1 right 21 increment 5 set font size 9 # Title tells what method used draw title "Used `draw image colorscale \scale'"