Testing the Image Manipulation Procedures

• Place the following expression in the definitions pane of DrRacket (the top one):

      (require (lib "fungraph.ss" "concabs"))
  

• Click Run on the tool bar.

• Go to the interaction pane and enter the expression:

      (filled-triangle -1 -1 0 1 1 -1)
  

• A black triangle should be displayed.