How to get whole and decimal part of a number?

Question

Given, say, 1.25 - how do I get "1" and ."25" parts of this number?

I need to check if the decimal part is .0, .25, .5, or .75.

Answer 1

$n = 1.25;
$whole = floor($n);      // 1
$fraction = $n - $whole; // .25

Then compare against 1/4, 1/2, 3/4, etc.

---

In cases of negative numbers, use this:

function NumberBreakdown($number, $returnUnsigned = false)
{
  $negative = 1;
  if ($number < 0)
  {
    $negative = -1;
    $number *= -1;
  }

  if ($returnUnsigned){
    return array(
      floor($number),
      ($number - floor($number))
    );
  }

  return array(
    floor($number) * $negative,
    ($number - floor($number)) * $negative
  );
}

The $returnUnsigned stops it from making -1.25 in to -1 & -0.25

Answer 2

This code will split it up for you:

list($whole, $decimal) = explode('.', $your_number);

where $whole is the whole number and $decimal will have the digits after the decimal point.

Answer 3

The floor() method doesn't work for negative numbers. This works every time:

$num = 5.7;
$whole = (int) $num;  // 5
$frac  = $num - $whole;  // .7

...also works for negatives (same code, different number):

$num = -5.7;
$whole = (int) $num;  // -5
$frac  = $num - $whole;  // -.7

Answer 4

Just to be different :)

list($whole, $decimal) = sscanf(1.5, '%d.%d');

CodePad.

As an added benefit, it will only split where both sides consist of digits.

Answer 5

a short way (use floor and fmod)

$var = "1.25";
$whole = floor($var);     // 1
$decimal = fmod($var, 1); //0.25

then compare $decimal to 0, .25, .5, or .75

Answer 6

Cast it as an int and subtract

$integer = (int)$your_number;
$decimal = $your_number - $integer;

Or just to get the decimal for comparison

$decimal = $your_number - (int)$your_number

Answer 7

There's a fmod function too, that can be used : fmod($my_var, 1) will return the same result, but sometime with a small round error.

Answer 8

PHP 5.4+

$n = 12.343;
intval($n); // 12
explode('.', number_format($n, 1))[1]; // 3
explode('.', number_format($n, 2))[1]; // 34
explode('.', number_format($n, 3))[1]; // 343
explode('.', number_format($n, 4))[1]; // 3430

Answer 9

Just a new simple solution, for those of you who want to get the Integer part and Decimal part splitted as two integer separated values:

5.25 -> Int part: 5; Decimal part: 25

$num = 5.25;
$int_part = intval($num);
$dec_part = $num * 100 % 100;

This way is not involving string based functions, and is preventing accuracy problems which may arise in other math operations (such as having 0.49999999999999 instead of 0.5).

Haven't tested thoroughly with extreme values, but it works fine for me for price calculations.

But, watch out! Now from -5.25 you get: Integer part: -5; Decimal part: -25

In case you want to get always positive numbers, simply add abs() before the calculations:

$num = -5.25;
$num = abs($num);
$int_part = intval($num);
$dec_part = $num * 100 % 100;

Finally, bonus snippet for printing prices with 2 decimals:

$message = sprintf("Your price: %d.%02d Eur", $int_part, $dec_part);

...so that you avoid getting 5.5 instead of 5.05. ;)

Answer 10

This is the way which I use:

$float = 4.3;    

$dec = ltrim(($float - floor($float)),"0."); // result .3

Answer 11

Brad Christie's method is essentially correct but it can be written more concisely.

function extractFraction ($value) 
{
    $fraction   = $value - floor ($value);
    if ($value < 0)
    {
        $fraction *= -1;
    }

    return $fraction;
}

This is equivalent to his method but shorter and hopefully easier to understand as a result.

Answer 12

I was having a hard time finding a way to actually separate the dollar amount and the amount after the decimal. I think I figured it out mostly and thought to share if any of yall were having trouble

So basically...

if price is 1234.44... whole would be 1234 and decimal would be 44 or

if price is 1234.01... whole would be 1234 and decimal would be 01 or

if price is 1234.10... whole would be 1234 and decimal would be 10

and so forth

$price = 1234.44;

$whole = intval($price); // 1234
$decimal1 = $price - $whole; // 0.44000000000005 uh oh! that's why it needs... (see next line)
$decimal2 = round($decimal1, 2); // 0.44 this will round off the excess numbers
$decimal = substr($decimal2, 2); // 44 this removed the first 2 characters

if ($decimal == 1) { $decimal = 10; } // Michel's warning is correct...
if ($decimal == 2) { $decimal = 20; } // if the price is 1234.10... the decimal will be 1...
if ($decimal == 3) { $decimal = 30; } // so make sure to add these rules too
if ($decimal == 4) { $decimal = 40; }
if ($decimal == 5) { $decimal = 50; }
if ($decimal == 6) { $decimal = 60; }
if ($decimal == 7) { $decimal = 70; }
if ($decimal == 8) { $decimal = 80; }
if ($decimal == 9) { $decimal = 90; }

echo 'The dollar amount is ' . $whole . ' and the decimal amount is ' . $decimal;

Answer 13

$x = 1.24

$result = $x - floor($x);

echo $result; // .24

Answer 14

If you can count on it always having 2 decimal places, you can just use a string operation:

$decimal = 1.25;
substr($decimal,-2);  // returns "25" as a string

No idea of performance but for my simple case this was much better...

Answer 15

To prevent the extra float decimal (i.e. 50.85 - 50 give 0.850000000852), in my case I just need 2 decimals for money cents.

$n = 50.85;
$whole = intval($n);
$fraction = $n * 100 % 100;

Answer 16

Try it this way... it's easier like this

$var = "0.98";

$decimal = strrchr($var,".");

$whole_no = $var-$decimal;

echo $whole_no;

echo str_replace(".", "", $decimal);

Answer 17

You could also use something like this:

preg_match("/([0-9]+)\.([0-9]+)/", $number, $matches);

Answer 18

If you want the two halves to be explicitly type cast, then sscanf() is a great call.

Code: (Demo)

var_dump(sscanf(1.25, '%d%f'));

Output:

array(2) {
  [0]=>
  int(1)
  [1]=>
  float(0.25)
}

---

Or you can assign the two variables individually:

sscanf(1.25, '%d%f', $int, $float);
var_dump($int);
var_dump($float);

---

Casting the decimal portion as a float is particularly useful when, say, converting decimal expression of hours to hours and minutes. (Demo)

$decimalTimes = [
    6,
    7.2,
    8.78,
];

foreach ($decimalTimes as $decimalTime) {
    sscanf($decimalTime, '%d%f', $hours, $minutes);
    printf('%dh%02dm', $hours, round($minutes * 60));
    echo "\n";
}

Output:

6h00m
7h12m
8h47m  // if round() was not used, this would be 8h46m

Answer 19

Not seen a simple modulus here...

$number         = 1.25;
$wholeAsFloat   = floor($number);   // 1.00
$wholeAsInt     = intval($number);  // 1
$decimal        = $number % 1;      // 0.25

In this case getting both $wholeAs? and $decimal don't depend on the other. (You can just take 1 of the 3 outputs independently.) I've shown $wholeAsFloat and $wholeAsInt because floor() returns a float type number even though the number it returns will always be whole. (This is important if you're passing the result into a type-hinted function parameter.)

I wanted this to split a floating point number of hours/minutes, e.g. 96.25, into hours and minutes separately for a DateInterval instance as 96 hours 15 minutes. I did this as follows:

$interval = new \DateInterval(sprintf("PT%dH%dM", intval($hours), (($hours % 1) * 60)));

I didn't care about seconds in my case.

Answer 20

val = -3.1234

fraction = abs(val - as.integer(val) )