如何计算数组中元素的总和和平均值？

Question

我在添加数组的所有元素以及将它们取平均值时遇到了问题。我该怎么做并用我现在拥有的代码实现它？这些元素应该定义如下。<script type="text/javascript">//<![CDATA[var i;var elmt = new Array();elmt[0] = "0";elmt[1] = "1";elmt[2] = "2";elmt[3] = "3";elmt[4] = "4";elmt[5] = "7";elmt[6] = "8";elmt[7] = "9";elmt[8] = "10";elmt[9] = "11";// Problem herefor (i = 9; i < 10; i++){  document.write("The sum of all the elements is: " + /* Problem here */ + " The average of all the elements is: " + /* Problem here */ + "<br/>");}   //]]></script>

Answer 1

var sum = 0;

for( var i = 0; i < elmt.length; i++ ){

    sum += parseInt( elmt[i], 10 ); //don't forget to add the base

}

var avg = sum/elmt.length;

document.write( "The sum of all the elements is: " + sum + " The average is: " + avg );

只需遍历数组，因为您的值是字符串，因此必须先将它们转换为整数。平均值就是值的总和除以值的数量。