JavaScript - Need Help With Simple Javascript Calculator. (first Time With Js)

Hello, I'm new here but not new to programming, I do some but only basic stuff. I know I could do this project in other languages but I'm not good with Java yet which seems like it would be the best for this request..

I am trying to implement a time calculator onto my website with preset times to tell how long it would take to make troops. Say you want to make 100 Catapults and each Catapult takes one minute and ten seconds to make, I would like to be able to show the time in days/hours/minutes preferably in the format of 0:00:00. I would like it so someone can type in the amount of troops they want. There are Infantry that take 0:00:22, Cavalry that take 0:00:52, Archers that take 0:00:35 and Catapults that take 0:01:10.

I have tried to do this and search for things that could help but I didn't find much.. It would be greatly appreciated if someone could help me with this.

I have been having problems adding checkboxes and option selects in the same function..

Here's what I have.

Code:

  <script type="text/javascript">
        function bonuscalc() {
            var aaaa = document.getElementById("aaaa").value;
            var bbbb = document.getElementById("bbbb").value;
	    var cccc = document.getElementById("cccc").value;
	    if (dddd.checked){
		var dddd = document.dddd.value = 2;
		} 
		else {
		var dddd = document.dddd.value = 1;
		}
	    var eeee = document.getElementById("eeee").value;
            var bonus = aaaa* bbbb * dddd * cccc * eeee;
	    var roundbonus = Math.round(bonus*10)/10;
            
            document.getElementById("roundbonus").value = roundbonus;
        }

    </script>

Javascript first.. The part I'm not sure about is the if/else part for checbox.

Now the html:

Code:

<form action="" id="calc1">
<table width="100%">
<tbody>
<tr>
<td>A status:   <select id="aaaa">
      		 		<option value="1.1">A1</option>
        	    	        <option value="1.02">A2</option>
        			<option value="1">A3</option>
        			<option value="0.95">A4</option>
   				</select>  
</td>   
 <td>B status: <select id="bbbb">
                        <option value="1">0%</option>
                        <option value="0.99">1%</option>
                        <option value="0.98">2%</option>
                        <option value="0.97">3%</option>
                        <option value="0.96">4%</option>
                        <option value="0.95">5%</option>
                        <option value="0.94">6%</option>
                        <option value="0.93">7%</option>
                        <option value="0.92">8%</option>
                        <option value="0.91">9%</option>
                        <option value="0.90">10%</option> 
                      </select>    
</td>
            
<td>E status:<input id="eeee" type="text" />
</td>

<td>D status:   <input id="dddd" name="dddd" type="checkbox">
</td>
                
<td>C status:   <select id="cccc">
        	          <option value="1">No</option>
                          <option value="1.2">Yes</option>
   		        </select>
</td>
</tr>                          
<tr>
<td width="100%">
     <input type="button" value="Submit" onclick="bonuscalc()" />
     <br /> 
 Result: <input type="text" readonly="readonly" id="roundbonus" />
</td>
</tr>
</tbody>
</table>
</form>

I hope it's not too confusing.
The idea is to assign value 2 if the checkbox is checked and value 1 is it isn't..

I am trying to make a fairly simple program for practicing for a mid-term that is coming up in my intro to programming class and I need some help figuring out how to create the function/setting up the variables. Essentially what the code is, is a program that adds up the values put in 5 text boxes, the values from checkboxes that are selected, and the value of a selected radio button.

I do not think I have the variables named correctly, and I have no idea how to create the function. I will post what I have so far so you can get a better idea of what it is I'm trying to make. It's so simple, just adding up everything. I just need help figuring out how to achieve that...
Here is the code I have so far:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">


<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Computer Price Caculator</title>
<script type="text/javascript">
function calc()

{
with( document.frmCom )
{
var P = setPerepherals.selectedIndex;
var S = setShipping.selectedIndex;
var total = P + S;
display.value = "Your systems total price is:" setPerepherals.value[P].text + setShipping.value[S].text + "\n Total:\t$" + total.toFixed(2);

}//end with
}//end calc()

</script>
<style type="text/css">
.auto-style1 {
margin-left: 17px;
}
</style>
</head>
<body background="PracticeMidterm/bg.jpg">

&nbsp;<center>
<h1>

<img src="PracticeMidterm/Computer.jpg" height="124" width="179">Computer Price Calculator</h1>
<hr class="auto-style1" style="width: 784px" />

<form name="frmCom">
<table style="border:thin black solid">
<tr>
<td colspan="2" width="700" align="center">
Processor (CPU): <input type="text" align="middle" name="textCPU"></input> <br/>
Motherboard: <input type="text" name="textMotherboard" ></input><br/>
Case: <input type="text" name="textCase" ></input><br/>
Power Supply: <input type="text" name="textPowersupply" ></input><br/>
Monitor: <input type="text" name="textMonitor" ></input>
</td></tr>
<tr>
<td align="center"><hr width="500" align="center" /></td>
</tr>
<tr>
<td colspan="1" align="center">
Perepherals:
<input type="checkbox" align="middle" name="checkboxKeyboard" value="25.00" onclick="setPerepherals()" >Keyboard ($25.00)</input>
<br/><input type="checkbox" align="middle" name="checkboxMouse" value="10.00" onclick="setPerepherals()" >Mouse ($10.00)</input>
<br/><input type="checkbox" align="middle" name="checkboxTablet" value="60.00" onclick="setPerepherals()" >Tablet ($60.00)</input>

</td>
</tr>
<tr>
<td align="center"><hr width="500" align="center" /></td>
</tr>
<tr>
<td colspan="1" align="center">
Shipping:
<input type="radio" align="middle" name="radShipping" value="5.00" onclick="setShipping()" >Ground ($5.00)</input>
<br/><input type="radio" align="middle" name="radShipping" value="10.00" onclick="setShipping()" >Second Day Air ($10.00)</input>
<br/><input type="radio" align="middle" name="radShipping" value="15.00" onclick="setShipping()" >Overnight Air ($15.00)</input>
</td>
</tr>
<tr>
<td align="center"><hr width="500" align="center" /></td>
</tr>
<tr>
<td colspan="1" align="center"><input value="Calculate price" type="button" /></td>
</tr>
<tr>
<td colspan="1" align="center"><textarea name="display" rows="10" cols="40">Total Price:</textarea></td>
</tr>
</table>
*******For more information visit <a href="http://www.howstuffworks.com/pc.htm">How Computers Work.</a>*******
</form>
</center>
</body>
</html>

Hey,

This is my first post!

I'm trying to learn javascript and i have tried to create a simple calculator, I have a calculator that does
Code:

 x * x = x

but when i try to cut / paste it into another project it just refuses to work!
This is undoubtably VERY BASIC but any help is VERY much appreciated

Code:

 

<SCRIPT LANGUAGE="JavaScript">
<!-- Begin 
function fmtPrice(value) {
result="$"+Math.floor(value)+".";
var cents=100*(value-Math.floor(value))+0.5;
result += Math.floor(cents/10);
result += Math.floor(cents%10);
return result;
}
function compute() {
var total_price = (document.forms[0].cost.value)*(document.forms[0].qty.value);
document.forms[0].total_price.value=total_price;
var total_price = fmtPrice(total_price);
document.forms[0].total_price.value=total_price;
}
function resetIt() {
document.forms[0].cost.value="0";
document.forms[0].qty.value="0";
document.forms[0].total_price.value="";
}
// End -->
</SCRIPT>

Here is a link to the page - http://dl.dropbox.com/u/29087/Java%20Laptop%20Calc.html
( so you can view source code, saving me from posting it all here )

what am i doing wrong?!! man java is so much harder than VB!

Hi all,
I am creating a simple 3 field calculator that calculates net, vat and gross. The user has to input 2 of the 3 fields, hit calculate and it should fill the 3rd field.

I have so far succeeded with the net field (enter in gross and vat) but the other 2 throw up spurious results!

I have worked out these equations (they work on a calculator)
Net = G - (( G * V ) / ( V + 100 ))
VAT = (( G - N ) x 100 ) / N
Gross = N + ( N x ( V / 100 ))

Heres the code for the javascript
Code:

<script type="text/javascript">
function netvatgross_calc() {
var net = (Number(document.calc.gross.value))-(((Number(document.calc.gross.value)) * (Number(document.calc.vat.value)))/((Number(document.calc.vat.value))+100));
var net = net.toFixed(2);
document.calc.net.value=net;

var vat = (((Number(document.calc.gross.value))-(Number(document.calc.net.value)))*100)/(Number(document.calc.net.value));
var vat = vat.toFixed(2);
document.calc.vat.value=vat;

var gross = (Number(document.calc.net.value))+((Number(document.calc.vat.value))/100)*(Number(document.calc.net.value));
var gross = gross.toFixed(2);
document.calc.gross.value=gross;
}
</script>

Here's the work in progress


I am also wanting to add some code to throw up an error if less or more than 2 values have been entered.

What am I doing wrong?

Any help greatly appreciated!
Cheers
Dan

Hey guys. This should be extremely easy for you to answer. This is actually for an intro to computers class I am taking and I am completely stumped. Basically I have to create a really simple Pythagorean Theorem calculator and this is what I have so far:

[CODE]
<html>
<head>
<title>A Pythagoras Conversion</title>
</head>

<script type="text/javascript">

var right_leg, left_leg, hypotenuse;

alert ("This calculates the hypotenuse of a right-angled triangle using the Pytahgorean Thereom. Press <OK> to continue!");

right_leg=prompt("Enter the length of the right leg.");

left_leg=prompt("Enter the length of the left leg.");


sq1 = right_leg*right_leg;
sq2 = left_leg*left_leg;

hypotenuse = math.sqrt(sq1 + sq2);


alert ("The Hypotenuse= ");

</script>

<body>
</body>
</html>
[CODE]

Everything works except for when it comes to it actually calculating. The calculation window never pops up. Please tell me what I am doing wrong in the calculation here....it is driving me nuts. :/

Thanks so much...

Hi guys i'm new to the world of programming and have been watching some videos on youtube by thenewboston to get to know Java. In one of his tutorials he shows you how to make a basic calculator but i wanted to improve it by adding the option to choose which operation you want to perform. However not being familiar with code i cannot think of a way to put it so that it is error free.I do also have a seperate class file which coresponds with the second paragraph.The errors appear in the if statements because of the characters * / - +. I am currently using eclipse to write my code as it is very useful for showing you your mistakes. Thanks in advance. Code:

Scanner tut7 = new Scanner(System.in);
double fnum, snum, answer;
System.out.println("Enter First Number Please:");
fnum = tut7.nextDouble();
System.out.println("Enter Second Number Please:");
snum = tut7.nextDouble();

Scanner opinput = new Scanner(System.in);
Operation OperationObject = new Operation();
System.out.println("Enter What Operation You Want to Perform: ");
String oper = opinput.nextLine();
OperationObject.calc(oper);

if (oper = * ){
answer = fnum * snum;
System.out.print("The Answer is: ");
System.out.println(answer);
}else{
if (oper = / ){
answer = fnum / snum;
System.out.print("The Answer is: ");
System.out.println(answer);
}else{
if (oper = + ){
answer = fnum + snum;
System.out.print("The Answer is: ");
System.out.println(answer);
}else{
if (oper = - ){

answer = fnum - snum;
System.out.print("The Answer is: ");
System.out.println(answer);
}else{
System.out.println("Invalid Operation!!!");
}
}
}

1 down vote favorite


I do have the countdown script (see link below) to display the time between current time and the date given in real-time.

However, I want to achieve to display the time difference between a given start and end time. Right now, it calculates from the current server time to the end time.

I want to be able to set up my own start time and end time.

Here is what I have:

http://jsfiddle.net/BgEtE/

thank you for help

I need help trying to figure out how to get my bmi calculator to work. I cant figure out what is wrong with my formula part and why it wont calculate the numbers you type in...pls help!

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>
<head>

<script type="text/javascript">

function calculateBMI()
{
var weight = numb(document.data.weight.value)
var height = numb(document.data.height.value)
var height2 = height2 * height2
var BMI = weight * 703 / (height2 * height2)

document.form.BodyMassIndex.value=custRound(BMI,1);
}

</script>
<title></title>

<style type="text/css">
div.c2 {text-align: center}
input.c1 {font-size: 8pt}
</style>
</head>
<body>
<div class="c2">
<form name="form" id="form"><input type="text" name="weight" size="4"> Weight (in Kilos) <input type="text" name="height" size="4"> Height (in Centimeters)<br>
<br>
<input type="text" name="BodyMassIndex" id="BodyMassIndex" size="4"> BMI <input type="button" class="c1" value="Calculate" onclick="calculateBMI()" name="button"> <input type="reset" class="c1" value="Clear Form"></form>
</div>
</body>
</html>

Hi all master and expert coders

I am working on a calculator which using the instructor's codes from the school. The problem that I having right now is the operator. I have successfully complete only the addition, but could not manage on subtraction and the rest operator. I hope experienced codes would help me out on this. Below is my codes.

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<script type="text/javascript">
function calculate() {
var value1 = parseInt(validate(document.getElementById("value1").value));
var value2 = parseInt(validate(document.getElementById("value2").value));
radioButtonCheck();
checkboxCheck();
dropDownListCheck();
document.getElementById("result").value = addition(value1, value2);
document.getElementById("result").value = subtraction(value1, value2);
document.getElementById("result").value = multiplication(value1, value2);
document.getElementById("result").value = division(value1, value2);
}

function validate(value) {
if (value == null || value == "") {
alert("Required Field");
return 0;
} else if (isNaN(value)) {
alert("Must be a number");
return 0;
}
else return value;
}

function addition(value1, value2){
return value1 + value2;
}
// trying to use the same addition return statement but fail.
function radioButtonCheck() {
if ((document.getElementById("radio1").checked == false)
&& (document.getElemtById("radio2").checked == false)) {
alert("Please select a radio button");
valid = false;
}
}
function checkboxCheck() {
if ((document.getElementById("cbox1").checked == false)
&& (document.getElementById("cbox2").checked == false)) {
alert("Please select a checkbox");
valid = false;
}
}
function dropDownListCheck() {
if ((document.getElementById("ddlOperator").selectedIndex == 0)) {
alert("Please select a operator");
valid = false;
}
}

</script>

<title>Calculator By Alsus</title>
</head>
<body>
<h2>Calculator</h2>
<table border = "1">
<tr>
<td>Value 1:</td>
<td><input type="text" id="value1" name="value1" /></td>
</tr>
<tr>
<td>Value 2:</td>
<td><input type="text" id="value2" name="value2" /></td>
</tr>
<tr>
<td>Operator:</td>
<td><input type="text" id="Operator" name="Operator" /></td>
</tr>
<tr>
<td><input type="radio" id="radio1" name="radio1" value="radio1" />Radio1<br /></td>
<td><input type="radio" id="radio2" name="radio2" value="radio2" />Radio2<br /></td>
</tr>
<tr>
<td><input type="checkbox" id="cbox1" name="cbox1" value="cbox1" />Checkbox 1<br /></td>
<td><input type="checkbox" id="cbox2" name="cbox2" value="cbox2" />Checkbox 2<br /></td>
</tr>
<tr>
<td>
<select id="ddlSelect">
<option value="+">+</option>
<option value="-">-</option>
<option value="*">*</option>
<option value="/">/</option>
</select>
</td>
<td>&nbsp;</td>
</tr>
<tr>
<td>Result:</td>
<td><input type="text" id="result" name="result" /></td>
</tr>
</table>
<input type="submit" id="btn_sub" name="btn_sub" value="Submit" onclick="calculate()" />
<input type="reset" id="btn_res" name="btn_res" value="Reset" />
</body>
</html>

I'm not sure what the code is to add this to javascript. I don't know if anyone can help me with this? Each numeric button should change the input box up at the top to whatever. When one of the operator buttons (+,-,*,/) is pressed, the value in the input box at the top should change to 0. Before an operator button is pressed, the value should be stored in a variable to keep track of the left-hand side of the equation. After it is pressed, the value should be stored in the right hand side variable.

Thanks

aaaaaa

This is what I have so far, but now I am stuck. My instructor wants the output value (Number Set C) to include Number Set A and Number Set B.

For instance, if Number Set A is "10" and you want to add Number Set B whose value is also "10", my instructor wants Number Set C to say "10 + 10 = 20".

Where am I going wrong, and what is the easiest way I can make this work while making as little changes as possible? Most of the code is what my instructor requires us to use.

Code:

<HTML>

 <HEAD>
  <TITLE>COMSC-100-1241 - Assignment #8 - Introducing "if" Logic - Programming Your Own Calculator</TITLE>

<SCRIPT LANGUAGE="text/JavaScript">
function Go(code){

var a
var b
var c
var x

a = parseFloat(document.getElementById("a").value);
b = parseFloat(document.getElementById("b").value);

if (code == 0){
  x = a + b
  c = a + " + " + b + " = " + x
  }
if (code == 1){
  x = a - b
  c = a + " - " + b + " = " + x
  }
if (code == 2){
  x = a * b
  c = a + " * " + b + " = " + x
  }
if (code == 3){
  x = a / b
  c = a + " / " + b + " = " + x
  }

document.getElementById("c").value = c;  
}
</SCRIPT>

 </HEAD>

<BODY>

<TABLE BORDER="1" WIDTH="500" ALIGN="center">
 <TR>
  <TD>

   <DIV ALIGN="left">
   <FORM NAME="calculator">
    <B>Instructions: </B> Type a number in the box for "Number Set #1". Then input a <I>second</I> number in the box for "Number Set #2". Click the "Calculate" button, and the sum of those two numbers will appear in the box for "Number Set #3".
     <BR>
     <BR>
    <B>Input Values: </B>
     <BR>
    <B>Number Set A:</B> <INPUT ID="a">
     <BR><BR>
    <B>Number Set B:</B> <INPUT ID="b" >
     <BR><BR>
    <INPUT TYPE="Submit" VALUE="Add" OnClick="Go(0);">
    <INPUT TYPE="Submit" VALUE="Subtract" OnClick="Go(1);">
    <INPUT TYPE="Submit" VALUE="Multiply" OnClick="Go(2);">
    <INPUT TYPE="Submit" VALUE="Divide" OnClick="Go(3);">
     <BR><BR>
    <B>Output Value: </B>
     <BR>
    <B>Number Set C:</B> <INPUT ID="c" SIZE="50">
   </FORM>
   </DIV>
   </FORM>

  </TD>
 </TR>
</TABLE>

</BODY>
</HTML>

Hello everyone, wondering if I could get some help. I have not done anything with html and javascript until this afternoon and funnily enough I'm struggling a tad
I am creating a free website about the dangers of chocolate for dogs. Basically I need a calculator to calculate the toxic amount for the user input of their dogs weight in kgs. I figured doing one for each type of chocolate would be easier than doing something where a box was ticked for each type of chocolate so have been trying to do one for milk chocolate first.
This is my feeble attempt, it looks good but doesnt work, my javascript is clearly majorly wrong somewhere!
<html>
<head>
<script language="JavaScript">

function calc(form)
{
var f = parseFloat(form.kg.value);
var T = 0;
T = (f/0.45)*28.35;
form.answer.value = T;
}
// done hiding from old browsers -->
</script>
</head>
<body>
<FORM>
<h2>Toxic dose of milk chocolate</h2>
Enter dogs weight in kg:
<INPUT NAME="kg" VALUE="0" MAXLENGTH="100" SIZE=25>
<p>
Click to calculate toxic dose in grammes:
<INPUT NAME="calc" VALUE="Calculate" TYPE=BUTTON
onClick=kg(this.form)>
<p>
Toxic amount of milk chocolate is:
<INPUT NAME="g" READONLY SIZE=25>
</FORM>
</body>
</html>
Can anybody help?
Thanks in advance.