doubleval()
Introduction
The doubleval() function is a built-in function in PHP that converts a variable to a float. It is an exact alias for the floatval() function, as PHP treats float and double as identical types.
Syntax
The syntax of the doubleval() function is as follows:
The PHP syntax of the doubleval()
doubleval(mixed $var): floatThe function takes a single parameter, $var, which is the variable to be converted to a float. The function returns the float value of the variable, or 0.0 if the variable cannot be converted.
Example Usage
Here is an example of how to use the doubleval() function in PHP:
Example of PHP doubleval()
<?php
$var1 = "3.14159";
$var2 = 42;
$var3 = true;
$var4 = "not a number";
echo doubleval($var1) . "\n"; // output: 3.14159
echo doubleval($var2) . "\n"; // output: 42.0
echo doubleval($var3) . "\n"; // output: 1.0 (true is converted to 1.0)
echo doubleval($var4) . "\n"; // output: 0.0 (cannot convert "not a number" to a double)
?>In this example, we define four variables with different data types: $var1 is a string, $var2 is an integer, $var3 is a boolean, and $var4 is a string that cannot be converted to a float. We then use the doubleval() function to convert each variable to a float and output the result. The output shows the float value of each variable, or 0.0 if the variable cannot be converted.
Conclusion
The doubleval() function is a useful tool for converting a variable to a float in PHP. It can be used to convert strings, integers, and booleans to floats, among other data types. By using this function, developers can ensure that their code is working with the correct data types and avoid errors that may occur when working with mixed data types. Note that floatval() is the standard and preferred name in modern PHP.
Practice
What does the doubleval() function in PHP do?