/*
* ============================================================
* Title: Reusable Floating-Point Range Generator in PHP
* ============================================================
*
* PHP's built-in range() function is primarily intended for
* integers and characters. While it can work with floats,
* precision issues may occur when repeatedly adding step values.
*
* Best Practices:
* - Validate all input parameters.
* - Use strict typing.
* - Avoid accumulating floating-point errors in loops.
* - Calculate each value from its index.
* - Return a reusable array of floating-point numbers.
*/
declare(strict_types=1);
/**
* Generates a range of floating-point numbers.
*
* @param float $start Starting value (inclusive).
* @param float $end Ending value (inclusive).
* @param float $step Increment between values.
*
* @return array<float>
*/
function floatRange(float $start, float $end, float $step): array
{
// Ensure the step size is valid.
if ($step <= 0) {
throw new InvalidArgumentException(
'Step must be greater than zero.'
);
}
// Determine how many values need to be generated.
$numberOfSteps = (int) round(($end - $start) / $step);
$result = [];
// Generate each value from its index rather than
// repeatedly adding the step value.
for ($index = 0; $index <= $numberOfSteps; $index++) {
$result[] = $start + ($index * $step);
}
return $result;
}
// ------------------------------------------------------------
// Example Usage
// ------------------------------------------------------------
$values = floatRange(
start: 1.0,
end: 2.0,
step: 0.2
);
print_r($values);
/*
run:
Array
(
[0] => 1
[1] => 1.2
[2] => 1.4
[3] => 1.6
[4] => 1.8
[5] => 2
)
*/
