HP 39GS hp 39gs_user's guide_English_E_HDPMG39AE13.pdf - Page 242

BOX ERASE FREEZE LINE PIXOFF PIXON TLINE 18-20 Example ARC 0;0;2;0;2π: FREEZE: Draws a circle centered at (0,0) of radius 2. The FREEZE command causes the circle to remain displayed on the screen until you press a key. Draws a box with diagonally opposite corners (x1,y1) and (x2,y2). BOX x1;y1;x2;y2: Example BOX -1;-1;1;1: FREEZE: Draws a box, lower corner at (-1,-1), upper corner at (1,1) Clears the display ERASE: Halts the program, freezing the current display. Execution resumes when any key is pressed. Draws a line from (x1, y1) to (x2, y2). LINE x1;y1;x2;y2: Turns off the pixel at the specified coordinates (x,y). PIXOFF x;y: Turns on the pixel at the specified coordinates (x,y). PIXON x;y: Toggles the pixels along the line from (x1, y1) to (x2, y2) on and off. Any pixel that was turned off, is turned on; any pixel that was turned on, is turned off. TLINE can be used to erase a line. TLINE x1;y1;x2;y2: Programming