Question

Just started working on a basic grid analysis algorithm in JavaScript but I have come up against an error that is perplexing me.

var max = 9; var testArray = new Array(   ['7', '3', '9', '6', '4', '1', '5', '2', '8'],   ['1', '8', '2', '7', '5', '3', '4', '6', '9'],   ['9', '5', '7', '3', '8', '2', '1', '4', '6'],   ['3', '1', '4', '9', '6', '7', '2', '8', '5'],   ['6', '2', '8', '5', '1', '4', '9', '3', '7'],   ['5', '4', '6', '2', '9', '8', '3', '7', '1'],   ['8', '7', '1', '4', '3', '5', '6', '9', '2'],   ['2', '9', '3', '1', '7', '6', '8', '5', '4'] );  function checkYoSelf(myGrid) {   var i; var j;   var horizLine = new String;   for( i = 0; i <= (max - 1); i++ ) {     for( j = 0; j <= (max - 1); j++) {       document.write(i+'<br />');       horizLine += myGrid[i][j];     }     var test = RegExp(i, 'ig');     var result = new Array(horizLine.match(test));     if( result.length > 1 ) {       alert('fail');     }       } }  html file has <a href='#' onclick='checkYoSelf(testArray);'>check</a> 

According to firebug myGrid[i] is undefined but I’m not sure why this should be.

What am I doing wrong?

Answer 1

Well, this is working for me… I’ve just replaced your ‘max’ variable to something more dynamic:

<script type='text/javascript'>     var testArray = new Array(         ['7', '3', '9', '6', '4', '1', '5', '2', '8'],         ['1', '8', '2', '7', '5', '3', '4', '6', '9'],         ['9', '5', '7', '3', '8', '2', '1', '4', '6'],         ['3', '1', '4', '9', '6', '7', '2', '8', '5'],         ['6', '2', '8', '5', '1', '4', '9', '3', '7'],         ['5', '4', '6', '2', '9', '8', '3', '7', '1'],         ['8', '7', '1', '4', '3', '5', '6', '9', '2'],         ['2', '9', '3', '1', '7', '6', '8', '5', '4']     );      function checkYoSelf(myGrid) {         var i;         var j;         var horizLine = new String;          var maxRows = myGrid.length;         for( i = 0; i < maxRows; i++ ) {             var maxColumns = myGrid[i].length;             for( j = 0; j < maxColumns; j++) {                 document.write(i+'<br />');                 horizLine += myGrid[i][j];             }              var test = RegExp(i, 'ig');             var result = new Array(horizLine.match(test));             if( result.length > 1 ) {                 alert('fail');             }         }     } </script>  <a href='#' onclick='checkYoSelf(testArray);'>check</a> 

Not sure what you’re trying to do with this, but at least it doesn’t give any error.