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<title>无标题文档</title>

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   var canvas = document.getElementById("Mycanvas");

   var context = canvas.getContext("2d");

   var x = 100;

   var y = 100;

   var a = 50;

   var b = 30

   //选择a、b中的较大者作为arc方法的半径参数

   var r = (a > b) ? a : b;

   var ratioX = a / r; //横轴缩放比率

   var ratioY = b / r; //纵轴缩放比率

   context.scale(ratioX, ratioY); //进行缩放（均匀压缩）

   context.beginPath();

   //从椭圆的左端点开始逆时针绘制

   context.arc(x , y , r, 0, 2 * Math.PI);

   context.fillStyle="#E2C1A7";

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