Example: Web-Based Bond Pricing Tool Using JavaScript
This example shows how to create a web application that calculates the price of a bond from a simple formula. It uses the MATLAB®
Production Server™ RESTful API and JSON Representation of MATLAB Data Types to depict an end-to-end workflow of using MATLAB
Production Server. You run this example by entering the following known values into a web interface:
The application calculates price (P) based on the following equation:
P = C * ( (1 - (1 + i)^-N) / i ) + M * (1 + i)^-N
You can use the sliders in the web application to price different bonds.Step 1: Write MATLAB Code
Write the following code in MATLAB to price bonds. Save the code using the filename pricecalc.m.
Step 2: Create a Deployable Archive with the Production Server Compiler App
To create the deployable archive for this example:
On the Apps tab, select the Production Server Compiler App.
In the Application Type list, select Deployable Archive.
In the Exported Functions field, add pricecalc.m.
Under Archive information, change pricecalc to BondTools.
Click Package.
The generated deployable archive, BondTools.ctf is located in the for_redistribution folder of the project.
Step 3: Place the Deployable Archive on a Server
Step 4: Enable Cross-Origin Resource Sharing (CORS) on the Server
Enable Cross-Origin Resource Sharing (CORS) by editing the server configuration file, main_config and specifying the list of domains origins from which requests can be made to the server. For example, setting the cors-allowed-origins option to --cors-allowed-origins * allows requests from any domain to access the server. See cors-allowed-origins and Edit the Configuration File for details.
Step 5: Write JavaScript Code using the RESTful API and JSON
Using the RESTful API and JSON Representation of MATLAB Data Types as a guide, write the following JavaScript® code. Save this code as a JavaScript file named calculatePrice.js.
Code:
calculatePrice.js
//calculatePrice.js : JavaScript code to calculate the price of a bond.
function calculatePrice()
{
var cp = parseFloat(document.getElementById('coupon_payment_value').value);
var np = parseFloat(document.getElementById('num_payments_value').value);
var ir = parseFloat(document.getElementById('interest_rate_value').value);
var vm = parseFloat(document.getElementById('facevalue_value').value);
// A new XMLHttpRequest object
var request = new XMLHttpRequest();
//Use MPS RESTful API to specify URL
var url = "http://localhost:9910/BondTools/pricecalc";
//Use MPS RESTful API to specify params using JSON
var params = { "nargout":1,
"rhs": [vm, cp, ir, np] };
document.getElementById("request").innerHTML = "URL: " + url + "<br>"
+ "Method: POST <br>" + "Data:" + JSON.stringify(params);
request.open("POST", url);
//Use MPS RESTful API to set Content-Type
request.setRequestHeader("Content-Type", "application/json");
request.onload = function()
{ //Use MPS RESTful API to check HTTP Status
if (request.status == 200)
{
// Deserialization: Converting text back into JSON object
// Response from server is deserialized
var result = JSON.parse(request.responseText);
//Use MPS RESTful API to retrieve response in "lhs"
if('lhs' in result)
{ document.getElementById("error").innerHTML = "" ;
document.getElementById("price_of_bond_value").innerHTML = "Bond Price: " + result.lhs[0].mwdata; }
else { document.getElementById("error").innerHTML = "Error: " + result.error.message; }
}
else { document.getElementById("error").innerHTML = "Error:" + request.statusText; }
document.getElementById("response").innerHTML = "Status: " + request.status + "<br>"
+ "Status message: " + request.statusText + "<br>" +
"Response text: " + request.responseText;
}
//Serialization: Converting JSON object to text prior to sending request
request.send(JSON.stringify(params));
}
//Get value from slider element of "document" using its ID and update the value field
//The "document" interface represent any web page loaded in the browser and
//serves as an entry point into the web page's content.
function printValue(sliderID, valueID) {
var x = document.getElementById(valueID);
var y = document.getElementById(sliderID);
x.value = y.value;
}
//Execute JavaScript and calculate price of bond when slider is moved
function updatePrice(sliderID, valueID) {
printValue(sliderID, valueID);
calculatePrice();
}
Step 6: Embed JavaScript within HTML Code
Embed the JavaScript from the previous step within the following HTML code by using the following syntax:
<script src="calculatePrice.js" type="text/javascript"></script>
Save this code as an HTML file named bptool.html.
Code:
bptool.html
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head lang="en">
<meta charset="UTF-8">
<title>Bond Pricing Tool</title>
</head>
<body>
<!-- Embed the JavaScript code here by referencing calculatePrice.js -->
<!-- <script src="calculatePrice.js" type="text/javascript"></script> -->
<script>
//Helper Code: Execute JavaScript immediately after the page has been loaded
window.onload = function() {
printValue('coupon_payment_slider', 'coupon_payment_value');
printValue('num_payments_slider', 'num_payments_value');
printValue('interest_rate_slider', 'interest_rate_value');
printValue('facevalue_slider', 'facevalue_value');
calculatePrice();
}
</script>
<h1><a>Bond Pricing Tool</a></h1>
<h2></h2>
This example shows an application that calculates a bond price from a simple formula.<p>
You run this example by entering the following known values into a simple graphical interface:<p>
<ul>
<li>Face Value (or value of bond at maturity) - M</li>
<li>Coupon payment - C</li>
<li>Number of payments - N</li>
<li>Interest rate - i</li>
</ul>
The application calculates price (P) based on the following equation:<p>
P = C * ( (1 - (1 + i)^-N) / i ) + M * (1 + i)^-N<p>
<hr>
<h3>M: Face Value </h3>
<input id="facevalue_value" type="number" maxlength="4" oninput="updatePrice('facevalue_value', 'facevalue_slider')"/>
<input type="range" id="facevalue_slider" value="0" min="0" max="10000" onchange="updatePrice('facevalue_slider', 'facevalue_value')"/>
<h3>C: Coupon Payment </h3>
<input id="coupon_payment_value" type="number" maxlength="4" oninput="updatePrice('coupon_payment_value', 'coupon_payment_slider')" />
<input type="range" id="coupon_payment_slider" value="0" min="0" max="1000" onchange="updatePrice('coupon_payment_slider', 'coupon_payment_value')"/>
<h3>N: Number of payments </h3>
<input id="num_payments_value" type="number" maxlength="4" oninput="updatePrice('num_payments_value', 'num_payments_slider')"/>
<input type="range" id="num_payments_slider" value="0" min="0" max="1000" onchange="updatePrice('num_payments_slider', 'num_payments_value')"/>
<h3>i: Interest rate </h3>
<input id="interest_rate_value" type="number" maxlength="4" step="0.01" oninput="updatePrice('interest_rate_value', 'interest_rate_slider')"/>
<input type="range" id="interest_rate_slider" value="0" min="0" max="1" step="0.01" onchange="updatePrice('interest_rate_slider', 'interest_rate_value')"/>
<h2>BOND PRICE</h2>
<p id="price_of_bond_value" style="font-weight: bold">
<p id="error" style="color:red">
<hr>
<h3>Request to MPS Server</h3>
<p id="request">
<h3>Response from MPS Server</h3>
<p id="response">
<hr>
</body>
</html>Step 7: Run Example
Assuming, the server with the deployed MATLAB function is up and running, open the HTML file bptool.html in a web browser. The default bond price is NaN because no values have been entered as yet. Try the following values to price a bond:
The resulting bond price is $1079.85
You can use the sliders in the tool price different bonds. Varying the interest rate results in the most dramatic change in the price of the bond.