Javascript Reference - JavaScript atan2() Method
The atan2() method returns the arctangent of
the quotient of its arguments.
The returned value is a numeric value between PI and -PI radians.
Browser Support
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atan2() |
Yes | Yes | Yes | Yes | Yes |
Syntax
Math.atan2(y, x);
Parameter
| Parameter | Description |
|---|---|
| y | Required. A number representing the y coordinate |
| x | Required. A number representing the x coordinate |
Return Value
A Number, from PI to -PI. Or NaN for illegal values.
Example
The following code shows how to calculate the arctangent of the quotient of its parameters.
<!--from w ww .j av a 2s . co m-->
<!DOCTYPE html>
<html>
<head>
<script type="text/javascript">
function doMath() {
var inputNum1 = document.form1.input1.value;
var inputNum2 = document.form1.input2.value;
var result = Math.atan2(inputNum1, inputNum2);
document.form1.answer.value = result;
}
</script>
</head>
<body>
<form name=form1>
Enter First Number: <input type="text" name="input1" size=10>
<br> Enter Second Number: <input type="Text" name="input2"
size=10> <br>
<br> <input type="button" value="Calculate" onClick='doMath()'>
<br> Answer: <input type="text" name="answer" size=10>
</form>
</body>
</html>