The graphing window shows the direction field of a differential equation that is selected by means of the pulldown menu [v].
In the "set target mode" the coordinates of the cursor are displayed in cyan and marked "target". Clicking on the window to place a square cyan target. This changes the mode to "set initial conditions". The cursor position is then read out in white. A click on the window now sets the initial condition of an integral curve, drawn in yellow. If the curve goes through the target it turns green.
Clear the solution curves using the [Clear Curves] key. Return to "set target mode" using the [Set Target] key.
© 2001 H. Hohn and H. Miller