Php: Get Number of Decimal Digits

PHP: get number of decimal digits

$str = "1.23444";
print strlen(substr(strrchr($str, "."), 1));

Show a number to two decimal places

You can use number_format():

return number_format((float)$number, 2, '.', '');

Example:

$foo = "105";
echo number_format((float)$foo, 2, '.', '');  // Outputs -> 105.00

This function returns a string.

How to get whole and decimal part of a number?

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

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

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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

Function to count decimal places with PHP

You'll have to make your own if you really want that function. It shouldn't be all that hard, though - just convert to a string, explode() on the ., and then take the length of the second element in the array.

Beware of floating point inaccuracy, though.

Drop decimal place without rounding value

You're trying to round a negative number. Rounding down a negative number with floor() will increase its absolute value; remember, -23.43(0) is less than -23.425!

Instead, you're looking to round up its value with ceil():

echo ceil(-23.425 * 100) / 100; // -23.42

This can be seen working here.

Check if number is decimal

You can get most of what you want from is_float, but if you really need to know whether it has a decimal in it, your function above isn't terribly far (albeit the wrong language):

function is_decimal( $val )
{
    return is_numeric( $val ) && floor( $val ) != $val;
}

How to cut decimal number using PHP

The expression you're trying to format is this:

($row['OK_05'] / $row['TotalMatch']) * 100

So whichever function you decide to use needs to go around that expression.

As to which function to use, you need to select one that returns a string, not a float.

If you use round, and your expression returns a float that rounds to a number with two zeros after the decimal point, the trailing zeros will not be displayed in the result. For example, echo round(92.0006829268, 2) will display 92, not 92.00. So don't use round if you need to be sure that two decimal places are always displayed. round is a math function, not a formatting function.

floor is really not useful at all here, as it returns a number with no decimal places.

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A simple way is to use sprintf as shown in some of the other answers.

echo sprintf("%.2f", ($row['OK_05'] / $row['TotalMatch']) * 100);

The first argument to sprintf is "%.2f", which is a format string indicating that the second argument should be displayed as a float with two decimal places. The second argument is your expression.

Using bcdiv as suggested in the other answer will also work, but it works a little differently that sprintf and will produce a slightly different result in some cases.

sprintf will round to the number of decimal places specified, so for example

echo sprintf("%.2f", 926.89 / 10);   // outputs 92.69

and bcdiv will truncate instead, so

echo bcdiv(926.89, 10, 2);           // outputs 92.68

Whichever one of those works for you, do that.

How to get number of digits in both right, left sides of a decimal number

I am lost on PHP semantics big time but I guess the following would serve your purpose without the String usage (that is at least how I would do in Java but hopefully cleaner):

Working code here: http://ideone.com/7BnsR3

Non-string solution (only Math)

Left side is resolved hence taking the cue from your question update:

$value = 12343525.34541;
$left = floor(log10($value))+1;
echo($left);

$num = floatval($value); 
$right = 0;

while($num != round($num, $right)) {
  $right++;
}

echo($right);

Prints

85

8 for the LHS and 5 for the RHS.

Since I'm taking a floatval that would make 155.0 as 0 RHS which I think is valid and can be resolved by String functions.

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