PRINT "アルキメデスの螺旋"
DEF x = t * COS(t)
DEF y = t * SIN(t)
SET WINDOW -22, 22, -22, 22
FOR t = 0 TO PI*7 STEP 0.0001
   PLOT LINES: x, y
NEXT t
END


###############################################


PRINT "対数螺旋"
LET  e = 2.71828182845904523536
DEF x = e^(t/10) * COS(t) - 1
DEF y = e^(t/10) * SIN(t)
SET WINDOW -24, 24, -24, 24
FOR t = -15 TO PI*10 STEP 0.0001
   PLOT LINES: x, y
NEXT t
END