在极坐标系中,以下方程表示的曲线称为玫瑰线(Rose curve):
或
当 n 是奇数时,玫瑰线有 n 个花瓣,称为 n 叶玫瑰。
当 n 是偶数时,玫瑰线有 2n 个花瓣,为 2n 叶玫瑰。
注:当 n 是分数或无理数时,图形要复杂一些,详见 Rose curve。
三叶玫瑰
with(plots):a:=1:
curve:=polarplot(a*sin(3*theta),thickness=3):
display(curve,scaling=constrained,title="three-leaved rose curve",tickmarks=[0,0]);
四叶玫瑰
with(plots):a:=1:
curve:=polarplot(a*sin(2*theta),thickness=3):
display(curve,scaling=constrained,title="four-leaved rose curve",tickmarks=[0,0]);
五叶玫瑰
with(plots):a:=1:
curve:=polarplot(a*cos(5*theta),thickness=3):
display(curve,scaling=constrained,title="five-leaved rose curve",tickmarks=[0,0]);
八叶玫瑰
with(plots):a:=1:
curve:=polarplot(a*cos(4*theta),thickness=3):
display(curve,scaling=constrained,title="eight-leaved rose curve",tickmarks=[0,0]);
二十叶玫瑰
with(plots):a:=1:
curve:=polarplot(a*sin(10*theta),thickness=3):
display(curve,scaling=constrained,title="twenty-leaved rose curve",tickmarks=[0,0]);