function setfocus() {
	document.calcform.x.focus();
}
function calc() {
	x = document.calcform.x.value;
 	y = calcfunc(x);
 	y = roundresult(y);
 	document.calcform.y.value = y
}
function calc_a() {
	x = document.calcform2.x.value;
 	y = calcfunc_a(x);
 	y = roundresult(y);
 	document.calcform2.y.value = y
}
function calc3() {
	x1 = document.calcform.x.value;
	x2 = document.calcform.x2.value;
 	y = calcfunc(x1,x2);
 	y = roundresult(y);
 	document.calcform.y.value = y;
}
function calc4() {
	a = document.calcform.x.value;
	b = document.calcform.x2.value;
	c = document.calcform.x3.value;
	d = b*b-4*a*c;
 	document.calcform.y0.value = roundresult(d);
 	if( d>=0 )
 	{
	 	document.calcform.y1.value = roundresult((-b+Math.sqrt(d))/(2*a));
	 	document.calcform.y2.value = roundresult((-b-Math.sqrt(d))/(2*a));
 	}
 	else
 	{
 		re = roundresult(-b/(2*a));
 		im = roundresult(Math.sqrt(-d)/(2*a));
	 	document.calcform.y1.value = re+' + i'+im;
	 	document.calcform.y2.value = re+' - i'+im;
 	}
 	b=-b;
 	document.calcform.y3.value = '('+b.toString()+' \xb1 sqrt('+d.toString()+')) / (2\xd7'+a.toString()+')';
}
function calc5() {
	x = document.calcform.x.value;
 	y = calcfunc(x);
 	y = roundresult(y);
 	if( x>0 ) y='±'+y;
 	document.calcform.y.value = y
}
function calc6() {
	x1 = document.calcform.x.value;
	x2 = document.calcform.x2.value;
	val=x2;
	if( x2<0 ) val=-val;
 	y = calcfunc(x1,val);
 	y = roundresult(y);
 	if( x2>0 && (x1/2)==Math.round(x1/2) ) y='±'+y;
 	if( x2<0 ) {
 		if( (x1/2)==Math.round(x1/2) )
 			y='NaN';
 		else
 			y=-y;
 	}
 	document.calcform.y.value = y;
}
function roundresult(x) {
 	y = parseFloat(x);
 	//y = Math.round(y*1.0e13)/1.0e13;
 	y = roundnum(y,10);
 	return y;
}
function roundnum(x,p) {
 	var n=parseFloat(x);
	var m=n.toFixed(p);
	var y=String(m);
	var i=y.length;
	while(i>0)
	{
		if(y.charAt(--i)=="0")
			y = y.slice(0,i);
		else
			break;
	}
	if(y.charAt(i)==".")
		y = y.slice(0,i);
	return y;
}
function gcd(a,b) {
	if(a>b) {
		tmp=a;
		a=b;
		b=tmp;
	}
	y=0;
	for(k=1; k<a; k++)
		y+=Math.floor(k*b/a);
	y<<=1;	
	y+=a+b-a*b;
	return Math.round(y);
}