[从头学数学]第101节比例的相关问题研究和修炼

正剧开始&＃xff1a;

星历2016年02月21日 14:45:36, 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]一起研究比例的相关问题。

>>> scale([2.4,1.6,60,&＃39;q&＃39;]);
2.4 : 1.6 &＃61; 60 : 40.0#求比例
def scale(array):if (len(array)&＃61;&＃61;4):# <0> : <1> &＃61; <2> : <3>if (array[0] &＃61;&＃61; &＃39;q&＃39;):array[0] &＃61; array[2]/array[3]*array[1];elif (array[1] &＃61;&＃61; &＃39;q&＃39;):array[1] &＃61; array[3]/array[2]*array[0];elif (array[2] &＃61;&＃61; &＃39;q&＃39;):array[2] &＃61; array[0]/array[1]*array[3];elif (array[3] &＃61;&＃61; &＃39;q&＃39;):array[3] &＃61; array[1]/array[0]*array[2];else:pass;print(round(array[0],3), &＃39; : &＃39;, round(array[1], 3), &＃39; &＃61; &＃39;,\round(array[2],3), &＃39; : &＃39;, round(array[3],3));else:print(&＃39;[<0> : <1> &＃61; <2> : <3>]&＃39;);return;

>>> scale([&＃39;q&＃39;, 320,1,10]);
32.0 : 320 &＃61; 1 : 10

>>> scale([24.3, &＃39;q&＃39;, 1, 20]);
24.3 : 486.0 &＃61; 1 : 20
>>> scale([1, 20, &＃39;q&＃39;, 11.76]);
1 : 20 &＃61; 0.588 : 11.76
>>> scale([1, 10, 19.6, &＃39;q&＃39;]);
1 : 10 &＃61; 19.6 : 196.0
>>> scale([500, 1, 35000, &＃39;q&＃39;]);
500 : 1 &＃61; 35000 : 70.0
>>> scale([3,8,15,40]);
3 : 8 &＃61; 15 : 40
>>> scale([2.5,0.5,2,0.4]);
2.5 : 0.5 &＃61; 2 : 0.4
>>>

function myDraw() { var config &＃61; new PlotConfiguration(); config.init(); config.setPreference(); config.setSector(1,1,1,1);config.axis2D(0, 0,180);var x, y;for (var i &＃61; 0; i <8; i&＃43;&＃43;) {x &＃61; i * 20;y &＃61; -x * 0.5;shape.fillCircle(x, y, 5);}}

function myDraw() { var config &＃61; new PlotConfiguration(); config.init(); config.setPreference(); config.setSector(1,1,1,1);config.axis2D(0, 0,180);var x, y;plot.scale(2, 2);for (var i &＃61; 0; i <8; i&＃43;&＃43;) {x &＃61; i*10;y &＃61; -300/ x;shape.fillCircle(x, y, 2);}}

>>> scale([7.8, &＃39;q&＃39;, 1, 4*10**5]);
7.8 : 3120000.0 &＃61; 1 : 400000
>>> 3120000/10**6
3.12
>>>

function myDraw() { var config &＃61; new PlotConfiguration(); config.init(); config.setPreference(); config.setSector(1,1,1,1);config.axis2D(0, 0,180);var x, y;var a &＃61; [[0,0], [-200, 0],[200,0],[0,250]];for (var i &＃61; 0; i

/**
* &＃64;usage 绘制点阵列
* &＃64;author mw
* &＃64;date 2016年02月21日 星期日 15:16:47
* &＃64;param
* &＃64;return
*
*/this.pointDraw &＃61; function(array, style) {style &＃61; style ? style : &＃39;black&＃39;;plot.save().setFillStyle(style);var a &＃61; new Array();a &＃61; array[0];if (a.length !&＃61; 2) {while (array.length > 0) { shape.fillCircle(array.shift(), array.shift(), 5); } }else { while (array.length > 0) { a &＃61; array.shift();shape.fillCircle(a[0], a[1], 5); } }plot.restore();}

function myDraw() { var config &＃61; new PlotConfiguration(); config.init(); config.setPreference(); config.setSector(1,1,1,1);config.axis2D(0, 0,180);var x &＃61; 1*37.8, y &＃61; 1.75*37.8, w &＃61; 2*37.8, h &＃61; 3.5 * 37.8;plot.setStrokeStyle(&＃39;red&＃39;);for (var i &＃61; 0; i <3; i&＃43;&＃43;) {shape.strokeRect(x, y, w, h);x &＃43;&＃61; w;}var h2 &＃61; 0.75*37.8;plot.strokeRect(0, -h2, w*3, h2);x &＃61; 1*37.8, y -&＃61; (h2&＃43;h);for (var i &＃61; 0; i <2; i&＃43;&＃43;) {shape.strokeRect(x, y, w, h);x &＃43;&＃61; w;}}

function myDraw() { var config &＃61; new PlotConfiguration(); config.init(); config.setPreference(); config.setSector(1,1,1,1);config.axis2D(0, 0,180);var x, y;var a &＃61; [[0,0], [-500, 0],[-500,300],[500,300], [500, -100]];var b &＃61; [];for (var i &＃61; 0; i

>>> scale([1.5,2.4,&＃39;q&＃39;, 4]);
1.5 : 2.4 &＃61; 2.5 : 4
>>> scale([6, 10.6, 14, &＃39;q&＃39;]);
6 : 10.6 &＃61; 14 : 24.733

本节到此结束&＃xff0c;欲知后事如何&＃xff0c;请看下回分解。