Question

我很确定我的代码是正确的，我很确定我的公式是正确的但是出于某种原因我得到的结果是7496238.570769714，应该是14.6969。这意味着一定有什么问题......我错过了什么，亲爱的代码大师？

我搜索了论坛，发现人们做了类似的任务，但遇到了不同的问题，我使用mozilla检查我的结果。

＆＃13;

var answer = 0;
var areaFromLength = function() {
  var a = document.getElementById("a").value;
  var b = document.getElementById("b").value;
  var c = document.getElementById("c").value;
  var x = (a + b + c) / 2;
  var answer = Math.sqrt(x * ((x - a) * (x - b) * (x - c)));
  document.getElementById("result").innerHTML = "<p>The area of the triangle is " + answer + "</p>";
  return false;
};

＆＃13;

<form id="tAreas">
  <p><input type="number" id="a" name="a" value="5"> length of triangle side 1</p>
  <p><input type="number" id="b" name="b" value="6"> length of triangle side 2</p>
  <p><input type="number" id="c" name="c" value="7"> length of triangle side 2</p>
  <button onclick="return areaFromLength()">Do the maths!</button>
</form>
<div id="result">
  <p>Your answer will appear here</p>
</div>

＆＃13;

Answer 1

数学时你的数字被视为字符串（5 + 6 + 7 = 567）。使用parseFloat：

＆＃13;

var answer = 0;
window.areaFromLength = function() {
  var a = parseFloat(document.getElementById("a").value);
  var b = parseFloat(document.getElementById("b").value);
  var c = parseFloat(document.getElementById("c").value);
  var x = (a + b + c) / 2;
  var answer = Math.sqrt(x * ((x - a) * (x - b) * (x - c)));
  document.getElementById("result").innerHTML = "<p>The area of the triangle is " + answer + "</p>";
  return false;
};

＆＃13;

<form id="tAreas">
  <p><input type="number" id="a" name="a" value="5"> length of triangle side 1</p>
  <p><input type="number" id="b" name="b" value="6"> length of triangle side 2</p>
  <p><input type="number" id="c" name="c" value="7"> length of triangle side 2</p>
  <button onclick="return areaFromLength()">Do the maths!</button>
</form>
<div id="result">
  <p>Your answer will appear here</p>
</div>

＆＃13;

使用heroni theorum在我的三角区域计算器中输出错误

1 个答案: