Develop Reference

Not showing result with decimal discount value

I have a discount jquery calculator plugin.It is working. But percentage is not working with decimal values like Eg: 5.45%, 10.50% , 15.70%, 20.75% etc.. I created a Codepen project for it. Please check this Codepen link https://codepen.io/coderco/pen/gOeReMQ . Here is my codes. Please help me..
HTML
<input type="text" id="Amount" value="">
<input type="text" value="10.45" id="Discount">
<input type="text" id="Result">
Script
$(document).on("change keyup blur", "#Discount", function() {
var main = $('#Amount').val();
var disc = $('#Discount').val();
var dec = (disc / 100).toFixed(2); //its convert 10 into 0.10
var mult = main * dec; // gives the value for subtract from main value
var discont = main - mult;
$('#Result').val(discont);
});

It's because of toFixed(2). When you divide the value by 100 then there are 4 decimal places.
For example:
Amount = 100, Discount = 10.45
dec = (10.45/100) = 0.1045 (Calling toFixed(2) changes it to 0.10 that means 10 instead of 10.45).
In my suggestion add toFixed(2) to the final answer (discount), Instead of while calculating.

How do i take values of 2 input fields which are numbers, then divide using Jquery and display the result to another input?

I have two input fields
<label>WEIGHT</label>
<input type="number" name="weight" id="weight" class="form-control" placeholder="weight in KG">
<label>HEIGHT</label>
<input type="number" name="height" id="height" class="form-control" placeholder="Height in Meters">
I want to take the value of weight and divide it by the height then assign the result to this input field in realtime using JQuery
<label>BMI</label>
<input type="text" name="bmi" id="bmi" class="form-control" placeholder="weight/height">
I have tried this but its not working
$(document).ready(function(){
var weight = $("#weight").val();
var height = $("#height").val();
var bmi = weight/height;
$("#bmi").val() = bmi;
});

When you use jQuery's .val to set a value, you need to pass the new value inside the parantheses, i.e: .val(newValue).
So you code should be like this:
$("#bmi").val(bmi);
Also, there's no sense in doing these calculations on document.ready, since the inputs will have no value. You need to move the code to a change event:
$("#height").change(function(){
var weight = $("#weight").val();
var height = $("#height").val();
var bmi = weight/height;
$("#bmi").val(bmi);
});

use parseInt like this:
$("#bmi").click(function (){
var weight = parseInt($("#weight").val());
var height = parseInt($("#height").val());
var bmi = weight/height;
$("#bmi").val(bmi);
}

Calculate sum and multiply its value

I'm calculating the sum of a and b and putting it in text box named sum.
After I enter a number in number text box, it should calculate the final = sum * number.
<input type="text" class="txt_1_0" name="a" />
<input type="text" class="txt_1_0" name="b" />
<input type="text" id="sum" name="sum" />
<input type="text" class="number" name="number" />
<input type="text" class="final" name="final" />
I tried the following:
$(document).ready(function() {
$(".txt_1_0").change(function() {
var total = 0.00;
var textbox3 = 0.00; // this gonna be your third textbox
$(".txt_1_0").each(function() {
total += parseFloat(this.value) / 5;
});
textbox3 = $("#sum").val((total).toFixed(2));
});
});
How do I get the number value and calculate final?

You haven't actually added any function that would do the final calculation. So to multiply the sum (subtotal) with number, do the following:
$(".number").change(function () {
var final = $("#sum").val() * $(this).val();
$('.final').val(final);
});
Here is a demo - note that I have removed the division by 5 from your previous function as it didn't make sense from the the way your question was asked.

Or you can use keyup event with this jQuery code Fiddle
<script type="text/javascript">
$(document).ready(function(){
$('input[type="text"]').on('keyup',function(){
var a=parseFloat($('.txt_1_0:first').val())
var b=parseFloat($('.txt_1_0:last').val())
if(a && b){$('#sum').val(a+b)}
var number=$('.number').val()
if(number){
$('.final').val($('#sum').val()*number)
}
})
})
</script>

Make the jquery script smart

There are 3 input fields.
Each has its own hidden input which helds value.
At this moment script works only for Bananas.(:-))
1 Banana is worth 1 banana OR 0.5 apple or 0.021 of a cookie(in other words 1 apple = 2 bananas, 46 bananas = cookie, 1 banana = 1 banana).
What I would like this script to do is to calculate values also for Apples and Cookies, and sum them up to show how much are they worth in "other" currencies.(for example show the price of 3 apples and 4 cookies in all 3 currencies)
I do realise that the code is very...well it would be a shame to call it code.
I just don't have any idea how to do it;
Any help would very appreciated.
Fiddle:
http://jsfiddle.net/eN7S6/9/
HTML:
<table>
<tr>
<td>
Apple<input name="inputone" id="inputone" class="calc" value="0"><span id="TotalOne"></span>
</td>
</tr>
<tr>
<td>
Banana<input name="inputtwo" id="inputtwo" class="calc" value="0"><span id="TotalTwo"></span>
</td>
</tr>
<tr>
<td>
Cookie<input name="inputthree" id="inputthree" class="calc" value="0"><span id="TotalThree"></span>
</td>
</tr>
</table>
<input name="multiplierone" id="multiplierone" class="calc" value="1" type="hidden" readonly>
<input name="multipliertwo" id="multipliertwo" class="calc" value="0.5" type="hidden" readonly>
<input name="multiplierthree" id="multiplierthree" class="calc" value="23" type="hidden" readonly>
<input type="button" id="update" value="Calculate" />
JQ:
$(document).ready(function() {
$('#update').click(function() {
var inputone = $('#inputone').val();
var multiplierone = $('#multiplierone').val();
var inputtwo = $('#inputtwo').val();
var multipliertwo = $('#multipliertwo').val();
var inputthree = $('#inputthree').val();
var multiplierthree = $('#multiplierthree').val();
var totalTotalOne = (inputtwo * multipliertwo);
var totalTotalTwo = (inputtwo);
var totalTotalThree = (inputtwo / multiplierthree / 2);
$('#TotalOne').text(totalTotalOne);
$('#TotalTwo').text(totalTotalTwo);
$('#TotalThree').text(totalTotalThree);
});
});

Well from what i gather from you description is that you want to get an amount that you have of a particular item. So if you have 10 bananas you want to calculate those 10 bananas against the other elements. The same goes for if you have 37 cookies you want to know how much its worth against the other items.
I believe that if you were to simplify your UI into two elements one being a input text field to enter amounts and another radio check collection, or it could be a selection field to select what type you have it will make better sense.
In your current setup you are not taking into account that your type(Apple, Banana, cookie) variable will change its only hard-coded to calculate bananas.
I quickly setup a jsbin to show you what i mean. Its just a start that may help you think of something else to do. Happy coding!
http://jsbin.com/EKisiGIK/10/edit

$(document).ready(function() {
$('#update').click(function() {
var inputone = parseFloat($('#inputone').val());
var multiplierone = parseFloat($('#multiplierone').val());
var inputtwo =parseFloat( $('#inputtwo').val());
var multipliertwo = parseFloat($('#multipliertwo').val());
var inputthree =parseFloat( $('#inputthree').val());
var multiplierthree = parseFloat($('#multiplierthree').val());
var totalTotalOne = (inputtwo * multipliertwo);
var totalTotalTwo = (inputtwo);
var totalTotalThree = (inputtwo / multiplierthree / 2);
$('#TotalOne').text(totalTotalOne);
$('#TotalTwo').text(totalTotalTwo);
$('#TotalThree').text(totalTotalThree);
});
});
Try this

One thing that you can do to make this problem simpler is to convert all currencies to a base currency before converting to their respective currencies. Using the example you have given i have converted all the currencies to their Cookie equivalent as it was the most valuable therefore removing the need to work with decimal values.
Change the HTML to
<input name="multiplierone" id="multiplierone" class="calc" value="23" type="hidden" readonly>
<input name="multipliertwo" id="multipliertwo" class="calc" value="46" type="hidden" readonly>
<input name="multiplierthree" id="multiplierthree" class="calc" value="1" type="hidden" readonly>
which is how many of each of the currencies it takes to make up one Cookie.
The following code can then be used to convert the currencies to Cookies
var base_total = inputone / multiplierone + inputtwo / multipliertwo + inputthree / multiplierthree;
var totalTotalOne = (base_total * multiplierone);
var totalTotalTwo = (base_total * multipliertwo);
var totalTotalThree = (base_total * multiplierthree);
this code will convert all the separate input values into their equivalent Cookie value. Once you have a total of all the fields as a cookie value it is a simple matter to convert that value back to all the respective currency values.
Fiddle

Calculating loan payment in Javascript

I am making a loan payment calculator on my website (www.kreditrunner.dk - In the bottom of the page).
EDIT: Problem solved with the following equation:
var princ = document.getElementById("amount").value;
var intr = document.getElementById("earlypercent").value/1200;
var term = document.getElementById("time").value;
document.getElementById("result").value = princ * intr / (1 - (Math.pow(1/(1 + intr), term)));
And also i used a keyup function instead. Cause when the key is pressed down, the input hasn't received the value yet, hence the wrong result :)
ORIGINAL POST:
I have my four inputs with respectively amount, interest rate per year in percent, payment period, and result.
<table>
<tr>
<td width="150">
<label for="amount">Lånebeløb (DKK)</label>
<input type="text" id="amount" name="amount" class="input-small">
<label for="earlypercent">ÅOP (%)</label>
<input type="text" id="earlypercent" name="earlypercent" class="input-small">
</td>
<td>
<label for="time">Løbetid (Mdr)</label>
<input type="text" id="time" name="time" class="input-small">
<label for="result"><b>Månedlig betaling (DKK)</b></label>
<input type="text" id="result" name="result" class="input-medium">
</td>
</tr>
</table>
For each of the first three input I have the listed calculations seen below which is derived from the following equation: http://www.wikihow.com/Calculate-a-Loan-Payment
$('#amount').keydown(function () {
var amount = document.getElementById("amount").value;
var earlypercent = document.getElementById("earlypercent").value;
var monthlypercent = earlypercent / 12 * 100;
var time = document.getElementById("time").value;
var negativetime = time * (-1);
var result = 1 + monthlypercent;
result = Math.pow(result, negativetime);
result = 1 - result;
result = monthlypercent / result;
document.getElementById("result").value = result * amount;
});
However, my result is weird as ****. As you can see when you try (e.g. with values, 1000, 10%, 12 months) the result is 8333.33 where it should have been around 83.33. Well actually it should be around 87.95.
So i could move the *100 in the montlypercent, however as you see when write an amount and tab to the next input field, the result changes even though the values are the same. Cant seem to get the equation right and the keydown function bothers me :/
Please help :)