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 v11 = document.first.va11.value;
	if(v11==0)
		a11 = -1*a11;

	var a12 = document.first.a12.value;
	var v12 = document.first.va12.value;
	if(v12==0)
		a12 = -1*a12;

	var a13 = document.first.a13.value;
	var v13 = document.first.va13.value;
	if(v13==0)
		a13 = -1*a13;

	var a21 = document.first.a21.value;
	var v21 = document.first.va21.value;
	if(v21==0)
		a21 = -1*a21;

	var a22 = document.first.a22.value;
	var v22 = document.first.va22.value;
	if(v22==0)
		a22 = -1*a22;

	var a23 = document.first.a23.value;
	var v23 = document.first.va23.value;
	if(v23==0)
		a23 = -1*a23;

	var a31 = document.first.a31.value;
	var v31 = document.first.va31.value;
	if(v31==0)
		a31 = -1*a31;

	var a32 = document.first.a32.value;
	var v32 = document.first.va32.value;
	if(v32==0)
		a32 = -1*a32;

	var a33 = document.first.a33.value;
	var v33 = document.first.va33.value;
	if(v33==0)
		a33 = -1*a33;

	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;
	
		var xa11 = aa11;
		document.first.ba11.value = aa11+"/"+deta;

		var xa12 = aa21;
		document.first.ba12.value = aa21+"/"+deta;

		var xa13 = aa31;
		document.first.ba13.value = aa31+"/"+deta;

		var xa21 = aa12;
		document.first.ba21.value = aa12+"/"+deta;

		var xa22 = aa22;
		document.first.ba22.value = aa22+"/"+deta;

		var xa23 = aa32;
		document.first.ba23.value = aa32+"/"+deta;

		var xa31 = aa13;
		document.first.ba31.value = aa13+"/"+deta;

		var xa32 = aa23;
		document.first.ba32.value = aa23+"/"+deta;

		var xa33 = aa33;
		document.first.ba33.value = aa33+"/"+deta;

		var bb1 = document.first.q1.value;
		var bb2 = document.first.q2.value;
		var bb3 = document.first.q3.value;

		document.first.bb1.value = bb1;
		document.first.bb2.value = bb2;
		document.first.bb3.value = bb3;
	
		var r1 = (xa11*bb1+xa12*bb2+xa13*bb3)/deta;
		var r2 = (xa21*bb1+xa22*bb2+xa23*bb3)/deta;
		var r3 = (xa31*bb1+xa32*bb2+xa33*bb3)/deta;

		document.first.r1.value = r1;
		document.first.r2.value = r2;
		document.first.r3.value = r3;
		document.first.rr1.value = r1;
		document.first.rr2.value = r2;
		document.first.rr3.value = r3;
	
	}
}


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

	for(var j=16; j<34; 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;
}