745.sagews

##Parametrized curve, with parametrization
##Enter the endpoints of the domain in lines 2 and 3
##Enter the function twice: once in line 4 with t as the variable, once in line 7 with s as the variable
t=var("t");
start=float(0);
stop=float(6*pi);
C = parametric_plot3d([ cos(t), sin(t), t ], (t,start,stop));
@interact
def example(s=(start,stop)):
    P = point([cos(s),sin(s),s], color = 'red')
    show(C + P)

##Parametrized curve, underlying point set
t=var("t");
parametric_plot3d([ cos(t), sin(t), t ], (t,0,6*pi))