怎么改变矢量场图的箭头类型（Mathematica）？

1、把矢量改为绿色。

VectorPlot[{Sin[y]*Cos[x + t], Cos[x]*Sin[y + t]},

 {x, -3, 3}, {y, -3,3}, VectorStyle -> Green]

2、去掉箭头：

VectorStyle -> {Arrowheads[0], Green}

3、双向箭头：

VectorStyle -> {"ArrowArrow", Green}

4、把箭头变小：

VectorStyle -> {Arrowheads[0.03], Green}

5、把箭头变成圆：

VectorStyle -> {Arrowheads[{{0.03, 1, Graphics[Circle[]]}}], Green}

6、把箭头的圆变小：

VectorStyle -> {Arrowheads[{{0.01, 1, Graphics[Circle[]]}}], Green}

7、箭头变成箭头，箭尾变成圆。

VectorStyle -> {Arrowheads[{{0.03, 1}, {0.01, 0, Graphics[Circle[]]}}], 

Green}