HP 48gII hp 48gII_user's manual_English_E_HDPMSG48E67_V2.pdf - Page 743

Animating a collection of graphics The calculator provides the function ANIMATE to animate a number of graphics that have been placed in the stack. You can generate a graph in the graphics screen by using the commands in the PLOT and PICT menus. To place the generated graph in the stack, use PICT RCL. When you have n graphs in levels n through 1 of the stack, you can simply use the command n ANIMATE to produce an animation made of the graphs you placed in the stack. Example 1 - Animating a ripple in a water surface As an example, type in the following program that generates 11 graphics showing a circle centered in the middle of the graphics screen and whose radius increase by a constant value in each subsequent graph. « RAD 131 R B 64 R B PDIM 0 100 XRNG 0 100 YRNG 1 11 FOR j ERASE (50., 50.) '5*(j-1)' NUM 0 '2*π' NUM ARC PICT RCL NEXT 11 ANIMATE » Begin program Set angle units to radians Set PICT to 131×64 pixels Set x- and y-ranges to 0-100 Start loop with j = 1 .. 11 Erase current PICT Centers of circles (50,50) Draw circle center r = 5(j-1) Place current PICT on stack End FOR-NEXT loop Animate End program Store this program in a variable called PANIM (Plot ANIMation). To run the program press J (if needed) @PANIM. It takes the calculator more than one minute to generate the graphs and get the animation going. Therefore, be really patient here. You will see the hourglass symbol up in the screen for what seems a long time before the animation, resembling the ripples produced by a pebble dropped on the surface of a body of quiescent water, appears in the screen. To stop the animation, press $. Page 22-27