var anni, rateanno, totrate, rata, capitale,interesse function checkNumber(input, min, max, msg) { msg = msg + " non corretto: " + input.value; var str = input.value; for (var i = 0; i < str.length; i++) { var ch = str.substring(i, i + 1) if ((ch < "0" || "9" < ch) && ch != '.' && ch != ',') { alert(msg); return false; } } var num = parseFloat(str) if (num < min || max < num) { alert(msg + " not in range [" + min + ".." + max + "]"); return false; } input.value = str; return true; } function computeField(input) { if (input.value != null && input.value.length != 0) input.value = "" + eval(v2dot(input.value)); computeForm(input.form); } function computeForm(form) { if ((form.payments.value == null || form.payments.value.length == 0) || (form.interest.value == null || form.interest.value.length == 0) || (form.principal.value == null || form.principal.value.length == 0)) { return 0; } if (!checkNumber(form.payments, 1, 99, "# anni") || !checkNumber(form.interest, .001, 99, "Interesse") ) { form.payment.value = "Invalid"; return 0; } var i = (form.interest.value); interesse=v2dot(form.interest.value)/100; rateanno=parseFloat(form.rat[form.rat.options.selectedIndex].value); i = i/rateanno/100; var pow = 1; anni=parseFloat(form.payments.value); totrate=(anni*rateanno); capitale=unformat(form.principal.value); for (var j = 0; j < totrate; j++) pow = pow * (1 + i); rata = ((capitale * pow * i) / (pow - 1)); form.payment.value=format(rata); form.principal.value=format(capitale); form.sommarate.value = format(rata*totrate); return 1; } function clearForm(form) { form.payments.value = ""; form.interest.value = ""; form.principal.value = ""; } function format(number) { number = (Math.round(number*100)/100); var oldNum = '' + number; var newNum = ''; decPos = oldNum.indexOf('.'); if(decPos >= 0) { newNum = ','+oldNum.substring(decPos+1,oldNum.length); } else { newNum = ''; decPos = oldNum.length; } for (var i=decPos; i>0; i -= 3) { if (i > 3) { newNum = '.'+oldNum.substring(i-3,i)+newNum; } else { newNum = oldNum.substring(i-3,i)+newNum; } } return newNum; } function unformat(number) { var oldNum = '' + number; var newNum = ''; var pPos = oldNum.indexOf('.'); while ( pPos>0) { newNum = oldNum.substring(0,pPos)+oldNum.substring(pPos+1,oldNum.length); oldNum=newNum; pPos = oldNum.indexOf('.'); } newNum=oldNum; return newNum; } function v2dot(number) { var oldNum = '' + number; var newNum = ''; var pPos = oldNum.indexOf(','); if ( pPos>0) newNum = oldNum.substring(0,pPos)+"."+oldNum.substring(pPos+1,oldNum.length); else newNum=oldNum; return newNum; } function CreateNewWindow() { var qinteresse=capitale*interesse/rateanno; var totinteressi=0.0; var totqcapitale=0.0; if(computeForm(document.forms[0])) { paWin = window.open("", "PianoAmmort",'scrollbars=yes,resizable=no,status=no,location=no,toolbar=no,menubar=no,width=500,height=500,top=0,left=0'); paWin.document.writeln(''); paWin.document.writeln('

'); paWin.document.writeln("Piano di ammortamento

"); paWin.document.writeln("

Sviluppo come da parametri impostati

"); paWin.document.writeln("

Capitale:	Euro "+format(capitale)+"
Tasso annuo:	"+interesse*100+"%
"); paWin.document.writeln("Rate per anno:	"+rateanno+"
Anni:	"+anni+"
Importo Rata:	"+format(rata)+"
Importo Totale:	"+format(rata*totrate)+"

"); paWin.document.writeln(""); paWin.document.writeln(""); for (var i=1; i<=totrate; i++) { qinteresse=capitale*interesse/rateanno paWin.document.writeln("") capitale-=(rata-qinteresse); totinteressi+=qinteresse; totqcapitale+=(rata-qinteresse); } paWin.document.writeln("") paWin.document.writeln("

Rata	Quota Interessi	Quota Capitale	Importo Rata	Debito Residuo
"+i+"	"+format(qinteresse)+"	"+format(rata-qinteresse)+"	"+format(rata)+"	"+format(capitale-(rata-qinteresse))+"
TOTALE	"+format(totinteressi)+"	"+format(totqcapitale)+"	*"+format(ratatotrate)+"**

"); } }