function calc(find) {
	var p = $('p').value;
	var f = $('f').value;
	var i = $('i').value/100;
	var n = $('n').value;
	var c = $('c').value;
	var eStr = '';
	var err = false;
	switch (find) {
		case 'p':
			if(!f) {eStr += '<p>You need to enter the Future Value</p>';err=true;}
			if(!i) {eStr += '<p>You need to enter the Annual Interest Rate</p>';err=true;}
			if(!n) {eStr += '<p>You need to enter the Number of Years</p>';err=true;}
			if(!c) {estr += '<p>You need to enter the Number of Periods in a year</p>';}
			if(!err) {$('p').value=Math.round((f/Math.pow(1+(i/c),(n*c)))*100)/100;}
			errShow('errMessage',err,eStr);
		break;
		case 'f':
			if(!p) {eStr += '<p>You need to enter the Present Value</p>';err=true;}
			if(!i) {eStr += '<p>You need to enter the Annual Interest Rate</p>';err=true;}
			if(!n) {eStr += '<p>You need to enter the Number of Years</p>';err=true;}
			if(!c) {estr += '<p>You need to enter the Number of Periods in a year</p>';err=true;}
			if(!err) {$('f').value=Math.round((p*Math.pow(1+(i/c),(n*c)))*100)/100;}
			errShow('errMessage',err,eStr);
		break;
		case 'i':
			if(!p) {eStr += '<p>You need to enter the Present Value</p>';err=true;}
			if(!f) {eStr += '<p>You need to enter the Future Value</p>';err=true;}
			if(!n) {eStr += '<p>You need to enter the Number of Years</p>';err=true;}
			if(!c) {estr += '<p>You need to enter the Number of Periods in a year</p>';err=true;}
			if(!err) {$('i').value=Math.round((c*(Math.pow((f/p),(1/(n*c)))-1))*10000)/100;}
			errShow('errMessage',err,eStr);
		break;
		case 'n':
			if(!p) {eStr += '<p>You need to enter the Present Value</p>';err=true;}
			if(!f) {eStr += '<p>You need to enter a Future Value</p>';err=true;}
			if(!i) {eStr += '<p>You need to enter the Annual Interest Rate</p>';err=true;}
			if(!c) {estr += '<p>You need to enter the Number of Periods in a year</p>';err=true;}
			if(!err) {$('n').value=Math.round((Math.log(f/p)/Math.log(1+(i/c)))/c*100)/100;}
			errShow('errMessage',err,eStr);
		break;
		default:
			errShow('errMessage',err,'There was an error resolving the function.');
		break;
	}
}