PHP atan()Functions
Examples
Return the arctangent of different numbers via the atan() function:
<?php
echo(atan(0.50) . "<br>");
echo(atan(-0.50) . "<br>");
echo(atan(5) . "<br>");
echo(atan(-5) . "<br>");
echo(atan(100) . "<br>");
echo(atan(-100));
?>
echo(atan(0.50) . "<br>");
echo(atan(-0.50) . "<br>");
echo(atan(5) . "<br>");
echo(atan(-5) . "<br>");
echo(atan(100) . "<br>");
echo(atan(-100));
?>
Run example »
Definition and Usage
The atan() function returnsargthe arctangent, the return value is a value between -Pi/2 and Pi/2.
Syntax
atan(arg);
| Parameters | Description |
|---|---|
| arg | Required. Specifies the parameter to process. |
Technical Details
| Return value: | argthe arctangent, in radians. |
|---|---|
| Return type: | Float |
| PHP version: | 4+ |
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