正剧开始:
星历2016年04月03日 09:50:19, 银河系厄尔斯星球中华帝国江南行省。
[工程师阿伟]正在和[机器小伟]一起研究[反比例函数 小结与复习题]。
<span style="font-size:18px;"> if (1) { var r = 20; config.setSector(1,1,1,1); config.graphPaper2D(0, 0, r); config.axis2D(0, 0,180, 1.5); //坐标轴设定 var scaleX = 2*r, scaleY = 2*r; var spaceX = 2, spaceY = 2; var xS = -10, xE = 10; var yS = -10, yE = 10; config.axisSpacing(xS, xE, spaceX, scaleX, 'X'); config.axisSpacing(yS, yE, spaceY, scaleY, 'Y'); var transform = new Transform(); //存放函数图像上的点 var a = [], b = [], c = [], d = []; //需要显示的函数说明 var f1 = 'y=2/x', f2 = 'y=2/|x|', f3 = 'y=-2/x', f4 = 'y=-2/|x|'; //函数描点 var x = xS; while (x <= xE) { if (Math.abs(x) <= 2) { x += 0.25; } else { x += 1; } if (x != 0) { //a.push([x, 2/x]); //b.push([x, 2/Math.abs(x)]); //c.push([x, -2/x]); d.push([x, -2/Math.abs(x)]); } } //存放临时数组 var tmp = []; //显示变换 if (a.length > 0) { a = transform.scale(transform.translate(a, 0, 0), scaleX/spaceX, scaleY/spaceY); //函数1 tmp = [].concat(a); shape.pointDraw(tmp, 'red'); tmp = [].concat(a); shape.multiLineDraw(tmp, 'pink'); plot.setFillStyle('red'); plot.fillText(f1, 200, -90, 200); } if (b.length > 0) { b = transform.scale(transform.translate(b, 0, 0), scaleX/spaceX, scaleY/spaceY); //函数2 tmp = [].concat(b); shape.pointDraw(tmp, 'blue'); tmp = [].concat(b); shape.multiLineDraw(tmp, '#22CCFF'); plot.setFillStyle('blue'); plot.fillText(f2, 200, -120, 200); } if (c.length > 0) { c = transform.scale(transform.translate(c, 0, 0), scaleX/spaceX, scaleY/spaceY); tmp = [].concat(c); shape.pointDraw(tmp, 'green'); tmp = [].concat(c); shape.multiLineDraw(tmp, '#CCFF22'); plot.setFillStyle('green'); plot.fillText(f3, 200, -150, 200); } if (d.length > 0) { d = transform.scale(transform.translate(d, 0, 0), scaleX/spaceX, scaleY/spaceY); tmp = [].concat(d); shape.pointDraw(tmp, 'orange'); tmp = [].concat(d); shape.multiLineDraw(tmp, '#CC8800'); plot.setFillStyle('orange'); plot.fillText(f4, 200, -180, 200); } } </span>
本节到此结束,欲知后事如何,请看下回分解。