//////////////////////////////////////////////////////////////////////
// Copyright(c) 1999 Madison Instruments, Inc.
// $Id: eqn.js,v 1.6 2004/11/18 20:53:15 db Exp db $
document.write("Try it here:<br>");
document.write("&nbsp;<INPUT type=text size=8 name=\"freq\">Hz");
document.write("&nbsp;=&nbsp;(");
document.write("<INPUT type=text size=8 name=\"speed\">Hz");
document.write("&nbsp;*&nbsp;<INPUT type=text size=6 name=\"spike\">&nbsp;cm-1)&nbsp;");
document.write("&nbsp;/&nbsp;<INPUT type=text size=7 name=\"laser\" value=\"15798\">cm-1");
document.write("&nbsp;<INPUT TYPE=button name=\"solve\" value=\"Solve\">");
document.write("<br>Blank fields are solved for, or frequency (default)");
document.write("<p>");
// solve f=(s*k)/l;
// or s=f*l/k;
function eqnSolve() {
	var k=parseFloat(document.eqn.spike.value);
	var s=parseFloat(document.eqn.speed.value);
	var l=parseFloat(document.eqn.laser.value);
	var f=parseFloat(document.eqn.freq.value);
	if (document.eqn.spike.value == "")
	{
		k=Math.round((l*f/s)*100)/100;
		document.eqn.spike.value = k;
	}
	else if (document.eqn.speed.value == "")
	{
		s=Math.round((l*f/k)*100)/100;
		document.eqn.speed.value = s;
	}
	else if (document.eqn.laser.value == "")
	{
		l=Math.round((s*k/f)*100)/100;
		document.eqn.laser.value = l;
	}
	else
	{
		document.eqn.freq.value = Math.round((k*s)/l*100)/100;
	}
}
/****
document.eqn.spike.onchange=eqnSolve;
document.eqn.laser.onchange=eqnSolve;
document.eqn.speed.onchange=eqnSolve;
document.eqn.freq.onchange=eqnSolve;
*****/
document.eqn.solve.onclick=eqnSolve;