用js，如何根据一个小数得出对应的分子/分母？

Question

比如给出0.5，如何计算得到 1/2 ？

Answer 1

function getFractionalExpression(value, threshold) {&nbsp; &nbsp; var i=1, j=1;&nbsp;&nbsp; &nbsp; while(Math.abs(i/j - value) > threshold) {&nbsp; &nbsp; &nbsp; &nbsp; if (i/j > value) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; j++;&nbsp; &nbsp; &nbsp; &nbsp; } else if(i/j < value) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; i++;&nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; }&nbsp; &nbsp; return i + '/' + j;}getFractionalExpression(0.25, 0.001);&nbsp; &nbsp; &nbsp;// "1/4"getFractionalExpression(0.33333, 0.001);&nbsp; // "1/3"getFractionalExpression(0.57142, 0.001);&nbsp; // "4/7"