function checkNumber(b,e,a,h){h=h+" field has invalid data: "+b.value;var g=b.value;for(var d=0;d<g.length;d++){var f=g.substring(d,d+1);if((f<"0"||"9"<f)&&f!="."){alert(h);return false}}var c=0+g;if(c<e||a<c){alert(h+" not in range ["+e+".."+a+"]");return false}b.value=g;return true}function computeField(input){if(input.value!=null&&input.value.length!=0){input.value=""+eval(input.value)}computeForm(input.form)}function computeForm(e){if((e.payments.value==null||e.payments.value.length==0)||(e.interest.value==null||e.interest.value.length==0)||(e.principal.value==null||e.principal.value.length==0)){return}if(!checkNumber(e.payments,1,480,"# of payments")||!checkNumber(e.interest,0.001,99,"Interest")||!checkNumber(e.principal,100,10000000,"Principal")){e.payment.value="Invalid";return}var c=e.interest.value;if(c>1){c=c/100}c/=12;var d=1;for(var b=0;b<e.payments.value;b++){d=d*(1+c)}e.payment.value=(e.principal.value*d*c)/(d-1);var f=e.payment.value;var a=f.split(".");e.payment.value=a[0]+"."+a[1].substring(0,2);e.totalint.value=(e.payment.value*e.payments.value)-e.principal.value;f=e.totalint.value;a=f.split(".");if(a[0]&&a[1]){e.totalint.value=a[0]+"."+a[1].substring(0,2)}}function clearForm(a){a.payments.value="";a.interest.value="";a.principal.value=""};