如何截取小数而不四舍五入？

Question

I'm trying to figure out how to cut off decimals without rounding the last digit.

For example, if my number is 1394.95861 , I would like it to show 1.39 - I don't want the last 9 to round up to a 0 or round down to an 8.

I've tried round, number_format, and all of those, but they all just round the last digit up.

if($number >= '1000') {

        $result = number_format(($number / 1000), 2);
        return $result;
}

Answer 1

I would not use >= '1000' since that treats $number as a string.

Try this:

if($number >= 1000) {
  $num = floor($number / 10) / 100;
  $result = number_format($num, 2);
  return $result . 'k';
}

I modified that based off of your question and code, but the key thing is floor being used to drop the remaining decimal points (hence why I divide by 10 first), then divide by those you wanted to keep (the divide by 100) to get your number.

EDIT: Calculational example

$number = 123456789.987654321;

Then, $number >= 1000 is true.

$number / 10 = 12345678.9987654321

And, the floor is

12345678

Divided by 100, we get

123456.78

Then, run through number format to get

123,456.78

And then add a k for the result:

123,456.78k

Modified code per chat:

function shorten_number($number) { 
  if($number >= 1000000000) { 
    $result = floor($number / 10000000) / 100; 
    return number_format($result) . 'b'; 
  } elseif($number >= 1000000) { 
    $num = floor($number / 10000) / 100; 
    $result = number_format($num, 2); 
    return $result . 'm'; 
  } elseif($number >= 1000) { 
    $num = floor($number / 10) / 100; 
    $result = number_format($num, 2); 
    return $result . 'k'; 
  } elseif($number < 1000) { 
    $result = $number; 
    return $result; 
  } 
}

Answer 2

do it manually -

$num = 12345.6789;

$number = explode('.', $num);

if (isset($number[1])) {
    if (isset($number[1][0])) {
        $number[0] .= '.'.$number[1][0];
        if (isset($number[1][1])) {
            $number[0] .= $number[1][1];
        }
    }
}
echo (float) $number[0];

Answer 3

Main idea is: create integer digit with proper digits using floor .

$number = 1394958.61;
if($number >= '1000') {

        $result = number_format((floor($number /10)/100), 2);
        echo $result . 'k';
}

Or using type casting.

        $result = number_format((intval($number /10)/100), 2);