What best practices should be followed to ensure accurate and reliable PHP calculations, especially when negative values are involved?

When dealing with negative values in PHP calculations, it is important to ensure accuracy and reliability by paying attention to data types and using appropriate functions for mathematical operations. One common issue is with subtraction, where negative values can lead to unexpected results if not handled properly. To address this, it is recommended to use type casting and built-in functions like abs() to ensure correct calculations.

// Example of ensuring accurate PHP calculations with negative values

// Define two variables with negative values
$number1 = -10;
$number2 = -5;

// Use abs() function to get the absolute values before performing subtraction
$result = abs($number1) - abs($number2);

// Output the result
echo "Result: " . $result;