Hello
I'd like to understand the rationale behind the ymin value in the get_minmax_data of a parametric curve that have always y=0:
sage: f(x)=sin(x)
sage: g(x)=0
sage: P=parametric_plot((f,g),(-pi/2,2*pi))
sage: P.get_minmax_data()['ymin']
-1.0
I would have expected ymin to be 0. Is is a bug or is it something I don't understand ?
