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 NumFormat(a){InString=_Trim(a);OutString="";InLength=InString.length;for(__x=InLength;__x!=0;__x--){if(OutString.length==3|OutString.length==7|OutString.length==11){OutString=","+OutString;OutString=InString.substring(__x-1,__x)+OutString}else{OutString=InString.substring(__x-1,__x)+OutString}}return OutString}function _Trim(a){astr=String(a);t_str=String("");LastCharAt=0;for(x=astr.length-1;x>=0;x--){if(astr.charAt(x)!=" "){LastCharAt=x+1;break}}return astr.substring(0,LastCharAt)}function computeForm(d){if((d.down.value==null||d.down.value.length==0)||(d.interest.value==null||d.interest.value.length==0)||(d.term.value==null||d.term.value.length==0)||(d.payment.value==null||d.payment.value.length==0)){return}if(!checkNumber(d.term,1,480,"# of payments")||!checkNumber(d.interest,0.001,99,"Interest")){d.principle.value="Invalid";return}var c=d.term.value*12;var e=d.interest.value;var b=d.down.value;var a=e;if(a==0){a=0.001}if(a>1){a=a/100}if(d.interest.value==""||d.down.value==""||d.payment.value==""||d.term.value==""){d.principle.value=""}else{a=(d.interest.value)/100;a=a/12;n=(d.term.value)*12;M=parseInt(_StrTran(d.down.value,",",""));tmp=(1/a)*(1-Math.pow(1/(1+a),n));tmp=(_StrTran(d.payment.value,",",""))*tmp;tmp=tmp+(_StrTran(d.down.value,",",""));tmp=Math.round(tmp*100)/100+M;d.principle.value=NumFormat(parseInt(tmp));if(d.principle.value==null||d.principle.value.length==0||d.principle.value=="NaN"){d.principle.value=""}}}function computeField(a){if(a.value!=null&&a.value.length!=0){a.value=""+NumFormat(parseInt(a.value))}}function _StrTran(f,c,e){var g=String(f);var d=String(c);var a=String(e);var b="";_len2chg=g.length;_len2lk4=d.length;for(_stepr=0;_stepr<_len2chg;_stepr++){if(g.substring(_stepr,_stepr+_len2lk4)==d){b+=a}else{b+=g.substring(_stepr,_stepr+_len2lk4)}}return b};