function isNum(args)
{
	args = args.toString();

	if (args.length == 0)
	return false;

	for (var i = 0;  i<args.length;  i++)
	{
		if ((args.substring(i,i+1) < "0" || args.substring(i, i+1) > "9") && args.substring(i, i+1) != "-")
		{
			return false;
		}
	}
	return true;
}

function check(df)
{
	var ad = df.value;
	if(!isNum(ad))
	{
		if(ad != "")
			ad = ad.substring(0,ad.length-1);

		df.value = ad;
	}
}

function madd()
{
	var a11 = document.first.a11.value;
	var a12 = document.first.a12.value;
	var a13 = document.first.a13.value;
	var a21 = document.first.a21.value;
	var a22 = document.first.a22.value;
	var a23 = document.first.a23.value;
	var a31 = document.first.a31.value;
	var a32 = document.first.a32.value;
	var a33 = document.first.a33.value;

	if( a11 == "" || a21 == "" || a31 == "" || a21 == "" || a22 == "" || a23 == "" || a31 == "" || a32 == "" || a33 == "" ) 
	{
		alert("Empty cells are present. Please fill proper values");
	}
	else
	{
		var aa11 = a22*a33-a23*a32;
		var aa12 = -(a21*a33-a23*a31);
		var aa13 = a21*a32-a22*a31;
		var aa21 = -(a12*a33-a13*a32);
		var aa22 = a11*a33-a13*a31;
		var aa23 = -(a11*a32-a12*a31);
		var aa31 = a12*a23-a13*a22;
		var aa32 = -(a11*a23-a13*a21);
		var aa33 = a11*a22-a12*a21;

		document.first.aa11.value = aa11;
		document.first.aa12.value = aa21;
		document.first.aa13.value = aa31;
		document.first.aa21.value = aa12;
		document.first.aa22.value = aa22;
		document.first.aa23.value = aa32;
		document.first.aa31.value = aa13;
		document.first.aa32.value = aa23;
		document.first.aa33.value = aa33;

		var deta = a11*aa11+a12*aa12+a13*aa13;
		document.first.deta.value = deta;

		var dar = aa11/deta;
		if(Math.round(dar) == dar)
			document.first.ba11.value = dar;
		else
			document.first.ba11.value = aa11+"/"+deta;

		dar = aa21/deta;
		if(Math.round(dar) == dar)
			document.first.ba12.value = dar;
		else
			document.first.ba12.value = aa21+"/"+deta;

		var dar = aa31/deta;
		if(Math.round(dar) == dar)
			document.first.ba13.value = dar;
		else
			document.first.ba13.value = aa31+"/"+deta;

		var dar = aa12/deta;
		if(Math.round(dar) == dar)
			document.first.ba21.value = dar;
		else
			document.first.ba21.value = aa12+"/"+deta;

		var dar = aa22/deta;
		if(Math.round(dar) == dar)
			document.first.ba22.value = dar;
		else
			document.first.ba22.value = aa22+"/"+deta;

		var dar = aa32/deta;
		if(Math.round(dar) == dar)
			document.first.ba23.value = dar;
		else
			document.first.ba23.value = aa32+"/"+deta;


		var dar = aa13/deta;
		if(Math.round(dar) == dar)
			document.first.ba31.value = dar;
		else
			document.first.ba31.value = aa13+"/"+deta;


		var dar = aa23/deta;
		if(Math.round(dar) == dar)
			document.first.ba32.value = dar;
		else
			document.first.ba32.value = aa23+"/"+deta;


		var dar = aa33/deta;
		if(Math.round(dar) == dar)
			document.first.ba33.value = dar;
		else
			document.first.ba33.value = aa33+"/"+deta;
	}
}


function color(test)
{
var cn =document.getElementsByTagName("input");
cn = cn.length;

	for(var j=19; j<37; j++)
	{
			var myI=document.getElementsByTagName("input").item(j);
			//myI.setAttribute("style",ch);
			myI.style.backgroundColor=test;
	}
}


function color1(test)
{
var myI=document.getElementsByTagName("table").item(0);
//myI.setAttribute("style",ch);
myI.style.backgroundColor=test;
}