js examples: arrays & loops jbwyatt.com

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1. fill an array with random nums - then print the array


<html>
<head>
   <script type="text/javascript">
   function go()
   {
      var myNums = new Array();
      var i, s;
      var o = document.getElementById("out");
      for ( i=0; i<10; i++)
        myNums[i] = Math.floor( Math.random() *100); 
        // number between 0 & .9999 times 100 and rounded down
            
      for ( i=0; i<myNums.length; i++)
        o.innerHTML += myNums[i] +" ";
   }          
   </script>

</head>
<body>

   <p onclick="go()"> mmm</p>

   <div id="out"></div>
 
</body>
</html>



2. fill an array incompletely

<html>
<head>
   <script type="text/javascript">
   function go()
   {
      var myNums = new Array();
      var i, s;
      var o = document.getElementById("out");
      for ( i=0; i<20; i+=2)
        myNums[i] = Math.floor( Math.random() *100); 
        // number between 0 & .9999 times 100 and rounded down
            
      for ( i=0; i<myNums.length; i++)
        o.innerHTML += myNums[i] +" ";
   }          
   </script>

</head>
<body>

   <p onclick="go()"> mmm</p>

   <div id="out"></div>
 
</body>
</html>


3. fill an array incompletely and only print defined elements

<html>
<head>
   <script type="text/javascript">
   function go()
   {
      var myNums = new Array();
      var i, s;
      var o = document.getElementById("out");
      for ( i=0; i<20; i+=2)
        myNums[i] = Math.floor( Math.random() *100); 
        // number between 0 & .9999 times 100 and rounded down
            
      for ( i in myNums)
        o.innerHTML += myNums[i] +" ";
   }          
   </script>

</head>
<body>

   <p onclick="go()"> mmm</p>

   <div id="out"></div>
 
</body>
</html>


4. array operations
   
   examples (end of page)
   
 sort, shift, unshift, pop , push, reverse, slice, splice