'slopefield' sketches a field of sample slopes for solutionsof , where g isany reasonably well-behaved function.
To enter the program, select program mode, 'NEW', then'MODE' 'REAL'. When 'TITLE?' appears, type in 'slopefield', then pressthe 'ENTER' key. When you have finished typing in the program, press theproram mode key. To run the program, select the program mode, 'RUN', with'slopefield' highlighted.
PLEASE NOTE: 'Goto', 'Label', 'Return', 'Range', 'ClrG','Line' and 'End' must be entered from the 'Command'; and all text, labeland variable names are typed in from 'ALPHA' mode. Everything else is enteredas a single keystroke on the calculator (for example, '+' is entered bypressing the '+' key).
When 'slopefield' is run, the calculator prompts the userfor xmin, xmax, xscl, ymin, ymax and yscl. The value of must be typed into the 'fncn' subroutine (within the 'slopefield' program)in the form, .For example, in the given program, ,so 'fncn' must contain the line 'f = -3*x*y'.
NOTICE: In writing this equation, you must use the ALPHAkey to type 'x' and 'y'; you cannot use the 'X' produced by the key.
Check: The slope field for ,for xmin = -3, xmax =3, xscl = 0.3, ymin = -2, ymax =2, yscl = 0.2 is sketchedon the right.