# Changing Calculation In Simple Interest Calculator

Aug 10, 2010

The exercise problem is to "MODIFY the code in the "calculate_click" event so interest is added to future value just once each year for the number of years that they were entered by the user". The calculation as you see it below assumes an amount is invested MONTHLY (not just once), and the interest is calculated accordingly. This is what I think the problem is trying to calculate: using a \$100 one time investment at 10% interest (compounded once annually) for one year = \$110 as the future value. For two years, the future value should equal \$121 (110 + (110*.10)). Okay, if my math is wrong, let me know. This is what I'm trying to get it to match to.

I have been able to modify the calculate_click function to compound the interest annually (it does it monthly now). Cool. I cannot get it to stop adding \$100 annually. See my math above? I think that's the answer. My manipulation of the code yields \$110 for the first year, \$231 for the second year, etc. The \$231 is incorrect cuz it adds an extra \$100. See, this is a simple interest calculator I can't figure out! The original code is below that calculates the investment as a monthly investment as opposed to one-time. To avoid confusion, I did not include any of my modifications. But yeah. I know that the major culprit is how the "for" loop is being executed. I've highlighted where I think the code needs to be changed, but I haven't changed it here. Note the first function is a shortcut to execute getElementbyID.

The Code:
var \$ = function (id) {
return document.getElementById(id);
} var calculate_click = function () {
var investment = parseFloat( \$("investment").value );
var annualRate = parseFloat( \$("rate").value );
var years = parseInt( \$("years").value );
\$("futureValue").value = ""; .....

## Simple Listbox OPTIONAL Value Calculation ?

Mar 14, 2009

Trying to figure out a problem with the "Optional" values in a list box so I am going to keep it as simple as I can..

I am trying to calculate the optional value of a list box in stead of programming it the long way around.

I created a list box with several peoples names, like John, Sue, and Mary.

I have assigned each name a numeric "optional" values

I know the code in the list box should be:

Normally, I would code this along the lines of:

But I want to figure out how to select the Optional Value from the list, and multiply it by time instead of doing the SELECTEDNAMELISTBOX=="John" route..

## Simple Calculation Doesn't Work

Nov 23, 2010

I have an input for Fahrenheit in degrees, then a button to start the calculations, then an input box for the result. But the result stays empty. where my Javascript code went wrong? I am modifying someone else's code form the Internet,I am guessing at how it works. [code]

## Simple Calculation - Error On Function Call

Aug 15, 2011

I have written the following javascript code which makes a simple calculation and writes between the <span> tags using Inner HTML

My code is:
Code:
<script type="text/javascript">
function hesapla() {
kredimiktari = document.hesapla.miktar.value
faiz = document.hesapla.faiz.value;
ayliktaksit1 = (kredimiktari * faiz) / kredivadesi;
geriodeme1 = kredimiktari * faiz;
document.getElementById('ayliktaksit').innerHTML = "<strong>Taksit / Ay :</strong>" + ayliktaksit1;
document.getElementById('geriodeme').innerHTML = "<strong>Taksit / Ay :</strong>" + geriodeme1;}
<form name="hesapla">

<input type="text" name="miktar" value="Kredi Miktarı" onfocus = "if (this.value == 'Kredi Miktarı') this.value = '';" onblur = "if (this.value == '') this.value = 'Kredi Miktarı';" />
<input type="text" name="vade" value="Kredi Vadesi" onfocus = "if (this.value == 'Kredi Vadesi') this.value = '';" onblur = "if (this.value == '') this.value = 'Kredi Vadesi';" />

<input type="text" name="faiz" value="Faiz Oranı" onfocus = "if (this.value == 'Faiz Oranı') this.value = '';" onblur = "if (this.value == '') this.value = 'Faiz Oranı';" />
<div id="gosterim"><span id="ayliktaksit"></span><span id="geriodeme"></span></div>
<input type='button' value='Hesapla' onClick='hesapla()'><br><br>
<img src="images/dot2.png" width="180" height="2" alt="dot"/>
</form></body></html>

I am really confused as similar code on Tizag web site works fine.
Code:
<script type="text/javascript">
function changeText(){
document.getElementById('boldStuff').innerHTML = 'Fred Flinstone';
}</script>
<p>Welcome to the site <b id='boldStuff'>dude</b> </p>
<input type='button' onclick='changeText()' value='Change Text'/>

## Calculator Calculation - 1st Number Entered Displaying It And Storing It In The Variable "memory"

Feb 13, 2011

This is calculator program that I have gotten stuck on. Here is where I think I am at:

The program is now taking the 1st number entered displaying it and storing it in the variable "memory".

Operation (+,-,*,/) is added to the memory in function action1() but then when the second number is entered it replaces memory with the second number. How can I get the variable memory to the whole string of 1st number,action, 2nd number?

Also once I do get that working correctly:

Wouldn't eval(document.calculator.display.value= memory) in my HTML for the "=" give me the calculation. (if I could figure out how to have memory store the 1st number and action1 and 2nd number all together) Or would eval(document.calculator.display.value) do it for me.

<html>

## JQuery :: Making A Simple Calculator

Sep 19, 2010

I'm getting started at javascript and jQuery, I want to make a calculator for my services, for example, checking a box will add value to a total.For example theres a textbox that asks how much gallons of paint will be used, the value of each gallon is 30 dollars, so the user can write for example 2 on the input and a div will output 60. I think that would be made with .change(), but in the demo of the documentations appears a selection list, and I can't figure out how to make an input work like that.

## Create A Simple Dynamic Calculator?

Jul 27, 2010

I am wanting to create a simple dynamic calculator.That when a radio button in the HTML <form> is selected is adds a value to the calculation and displays it live below.For example the select a package:

[] one [] two [] three

then they choose an extra's they want to add on:

[] one [] two [] three [] four

and below it displays this:

[ The name of package selected + value of it in (�) ] + The value of all the add ons they have selected in (�)

## Simple Calculator - Where To Add ParseInt Function

Oct 18, 2009

I need to create a simple calculator in Java. Below is what I have so far; it is not working currently and I'm not sure why. I also needed to add the parseInt function somewhere in the code but I'm not sure where.

import java.util.Scanner;
public class CalcDemo {
public static void main(String[] args){
}
private int valueA;
private int valueB;
private String operator;
private char operatorA;
public int getvalueA() {
return valueA;
} .....

## Keep Getting NaN On A Simple Form-based Calculator?

Nov 22, 2010

I keep getting a NaN on this form-based calculator I am trying to make... I can't figure out what I am doing wrong. Any input, or in this case "output", Here is the code:

Code:
<script type="text/javascript">
function calculateBudget()
{

[Code]....

## Getting Simple Instant Price Quote Calculator?

Jan 19, 2011

I am trying to come up with an instant price quote calculator in javascript.it would be a simple one with only three fields:

"label" -Number of Shirts
"label" -Number of Colors on Front
"label" -Number of Colors on Back
"button" calculate total
"results" total: \$xx per bagxx

total price would decrease based on the number of shirts (more volume) / increase based on the number of colors both front and back.

something i found online that is 100% what i want:[URL]i am not too familiar with javascript. ok tinkering with jquery but that's it.i am obviously not asking anyone to work for free but if someone could point me to a semblance of a solution, some code, something online that i could modify etc. i would love to learn javascript in the process and ideally come up with a working version of the calculator.

i tried to work with the .js from that website but it calls in some qq2.php page. so i haven't been able to replicate the solution. plus, i would assume that their price structure would be different than mine.

## Calculate Interest Earned Code?

Feb 8, 2011

I'm a JavaScript newbie and need help with code.Given principle, yearly interest rate and time in years, I need to calculate interest earned and the ending amount in the account at the end of time.

Formulas:

I=P*R*T
S=P+T

This is what I have which didn't work:

<script type="text/javascript">
var P,R,T,I,S;

[code]...

## Getting A Program That Will Compare Loans With Various Interest Rates?

Nov 15, 2011

monthly payment = c*r*(1+r)^n /(1+r)^n

## Bank Website - Calculating Loan Repayment With Interest

Jun 10, 2010

I am having a few problems with my JS, and now that the module has finished, I find myself struggling still. I am going to post my JS and the HTML page its related to. The site is a mock up for an assignment - basically, its a pretend bank website where a person applies for a loan, and all my JS does is work out if the applicant does the following correctly:

Enters repayment years 1 to 25
Enters a loan amount of 1000 to 250000
Checks a box for loan protection
Calculate button
Reset Button
Then tells the user what it is going to cost them from interest to total amount to be paid.

Javascript:
function init(){
var baserate=4.25;
var amount=parseInt(document.getElementById("loan").value);// end bracket missing - done
var repaymentyears=parseInt(document.getElementById("repaymentyrs").value);// end bracket missing - done
var rate;
var interest;
var loanprotect=5;
var total;
var monthlyrepayment=repaymentyears*12; .....

## Mortgage Calc Adding Extra Decimal Place To Interest Rate

Oct 12, 2009

I have a mortgage calc that is adding an extra decimal place to my interest rate. To see this in action go to: [URL]
Change the interest rate to 7.5
Click Calculate Payment
Click Create Amortization Chart
On the following screen you'll see a recap of your data and the interest rate will now say 7.55. Same thing happens if you enter 6.2. Next screen shows 6.22/. I've attached the html and js files in a zip.

## Numbers From A Text Box For Calculation

Mar 7, 2006

I have the two text boxes on a form, both of which a user enters a
number. I simple need to ADD THESE UP!

I know, its daft, but no matter what I do, it just adds them together.

Example: 1+1 is clearly 2, but it outputs 11!

An example of my code:

var loan = document.loandata.loan.value;
var other = document.loandata.other.value;

total = (loan+other);

## Future Date Calculation

Jan 7, 2007

I am trying to make a script that prints a date in the format Sunday
14th January 2007. Where the date that is displayed is the next sunday
3 weeks from now. For example today is 7th January. The script would
print Sunday 28th January 2007. It would read that all of this week
until next sunday when it would change to Sunday 4th February.

## Problem With Time Calculation

Feb 5, 2007

It's probably something with rounding off, or floating point problems.
I have a timer which is used when solving the Rubik's cube. It has to
measure an exact time, but the clock display I made shows a different
value than the actual time (also displayed after session: ...). I am
using the same variable for both displays. sometimes it's off by .02.

## Form Calculation Not Working?

Jan 4, 2010

I'm building a form that is calulated based on the options selected with a javascript form. This is my first attempt at something like this so I'm a bit lost at the final update.

First to be sure I'm on spot here is the javascript I'm using to update the form - <script>
function BDWcalc ()
{

[code]....

## Checking The Date Calculation?

Sep 22, 2011

I have a javascript that should convert any date into a number between 1 and 260. Based on the outcome of that calculation, a viewer is directed to a specific web page.How can I verify the calculation? How can I see what number javascript is arriving at so I can backtrack to the error? It is not serving up the correct page.

I have compared the results to a calculator on another website [URL] that uses a different script to calculate the same result -- that's why I am saying the end results are not correct. On the other website, scroll down to where you enter a date. It returns a name just above the date (example: July 25, 1970 returns Electric Star). The script I included above returns Yellow Sun. July 25, 1970 should = 68.

function calculate() {
if(!isValidDate())
return;

[code]....

## Auto Calculation Cost?

Aug 19, 2009

Please take a look at the picture below:When you enter the value of Volume and Unit Cost... it should automatically add up into Net Cost and VAT (including float number).

May 14, 2007

I currently have a web page that is building a web form from data contained in a SQL table. I need to do some calculations on the numbers that are populated into the form. I have used the following javascript code to successfully complete my calculations but I can only use this code at the bottom of my page because executing it at the top of my page the form fields are still empty. How would I use or modify the code I have to display the calc at the top of the web form. Example as follows:

<form method="POST" target="_self" name="dialer" enctype="text/plain">

Loan Amount: <input type="text" value="400000" name="loan" />
Interest Rate: <input type="text" value="1.00" name="apr" />
Amortization Term: <input type="text" value="480" name="term" />

</form>

<script language="JavaScript">

var princ = document.dialer.loan.value;
var term = document.dialer.term.value;
var intr = document.dialer.apr.value / 1200;

var output = princ * intr / (1 - (Math.pow(1/(1 + intr), term)));
var calc = (Math.round(output * 100)/100);

</script>

## Calculation The Value From Two Text Field

Nov 17, 2010

f
Code:
unction up(){
var inpt= document.getElementById("item_one").value
document.getElementById("aCom_total").value=Math.floor(inpt)
}
function up2(){
var inpt= document.getElementById("aCom_total").value
[Code]....

I input the valve 100 in textone my total =100 I input the value into 20 text two my total is not 120, but 10020

## Problem With Date Calculation In Form

Jul 20, 2005

I have a form which must calc the difference between 2 date fields and
return the result in a third field. I have the following code but it does
not seem to work. Can anyone tell this total newbie where he is going wrong
or suggest a more elegant way of doing this.

function doit(oForm, usrInp)
{
var one_day = 1000 * 60 * 60 * 24 ;

var userDate = new Date(usrInp)
var dueDate = new Date(usrInp)

diff = dueDate - userDate
oForm.diff.value = (diff/one_day) + ' days'
}

//-->
</script>
<body>
<form name="a">
<input type="text" name="userDate" >
<input type="text" name="dueDate" onblur='doit(this.form, this.value)'>
<input type="text" name="diff" onfocus=this.blur();>
</form>

## Real Text Size Calculation?

Jul 20, 2005

I've got a small problem here. I'm trying to write some code that would
generate a drop-down menue for me, where I'd just need to enter the
menu- and submenu items into an array. The items are to be displayed as
text. Now, I want to have the layers with the submenues to appear more
or less under the appropriate main menu items. For this I need to be
able to calculate how many pixels a given text uses up on the screen of
the user. That's all fine with IE and an unproportional font like
courier. The problem is, there is this nice setting that allows you to
change the diplay size of the text - which is pretty much disfunctional
in IE, but in mozilla, it works. Which means that I can't just say that
one letter in courier, size 2, is 4 pixels wide and be happy with my
calculation, because then somebody can just pop up with another text
diplay size and *boom* - my calculation is wrong again.

Now, is there a realistic way to find out how many pixels _exactly_ a
piece of text takes up on the user's screen? Or can I make the given
piece of text a DIV and then have some kind of document.divname.left
that gives me the actual location of this text?

## JQuery :: Looking For Price / Distance Calculation

May 6, 2010

I'm looking for a jquery tutorial which helps on calculating the distance between two points?

I've found a few javascript ones, but its breaking the rest of my jquery code!

does anyone know of anything? im using it to calculate a price for a specific distance traveled.

## Check Box Values Calculation + Display?

Aug 3, 2010

I'm creating this form that when you tick a checkbox, it adds the value of that checkbox to the running total. Then it displays the Calculation and Running total.

Code:
<html>