I want to have a PHP number formatted with a minimum of 2 decimal places and a maximum of 8 decimal places. How can you do that properly.
Update: I'm sorry, my question is say I have number "4". I wish for it to display as "4.00" and if I have "2.000000001" then it displays as "2.00" or if I have "3.2102" it will display as such. There is a NSNumber formatter on iPhone, what is the equivalent in PHP.
This formats the $n number for 8 decimals, then removes the trailing zero, max 6 times.
$s = number_format($n, 8);
for($i=0; $i<8-2; $i++) {
if (substr($s, -1) == '0')
$s = substr($s, 0, -1);
}
print "Number = $s";
Use sprintf() to format a number to a certain number of decimal places:
$decimal_places = 4;
$format = "%.${decimal_places}f";
$formatted = sprintf($format,$number);
I don't understand why you would want to display numbers to an inconsistent degree of accuracy. I don't understand what pattern you're trying to describe in your comment, either.
But let us suppose that you want the following behaviour: you want to express the number to 8 decimal places, and if there are more than 2 trailing zeroes in the result, you want to remove the excess zeroes. This is not much more difficult to code than it is to express in English. In pseudocode:
$mystring = string representation of number rounded to 8 decimal places;
while (last character of $mystring is a 0) {
chop off last character of $mystring;
}
Check the number format function:
<?php
$num = 43.43343;
$formatted = number_format(round((float) $num, 2), 2);
?>
http://php.net/manual/en/function.number-format.php
Using preg_match just get the zero ending with and then rtim it
<?php
$nn = number_format(10.10100011411100000,13);
preg_match('/[0]+$/',$nn,$number);
if(count($number)>0){
echo rtrim($nn,$number[0]);
}
Hope it will help you.
Related
Is there any function that easily echos an integer that is 15+ digits long?
The only way I've managed is like this:
$num = 123456789012345;
$num = number_format($num);
$num = str_replace(',', '', $num);
echo $num;
But even this way it is only accurate up to 17 digits. After the 16th digit the number isn't printed accurately (because as a float it starts getting inaccurate - see here).
EDIT: From the answers below I wrote ini_set('precision',40); and then echoed $num straight. All this did was to, simply put, not show the decimal point in the float number. And again after the 16th digit it starts getting inaccurate.
I also tried the other suggestion of changing it into an array and then iterating through it with str_split($num); and again the numbers were inaccurate from the 17th digit on!
The simplest solution would be to convert the integer into a string. I've tried:
$num = (string)$num;
//and
$num = strval($num);
But neither change anything and they act as if as they remained as an int??
My question is specifically why are the conversions into strings not working. Is there a way to turn the number into a string? Thanks
The only solution I can think of is changing the precision of floats in the php.ini
ini_set('precision', 25);
I don't know where you get those large numbers from, but I'd suggest a look into bc functions too!
The last thing I thought of is using the explode function to split the string into an array and interate through it.
EDIT: When all suggestions failed, your only choices are to check out the BC Math and/or GMP functions as well as MoneyMath. The BigInteger package should also do the trick, which uses GMP and BC.
Well, you see, it's not an "int" as you claimed :)
echo PHP_INT_MAX; // echoes 9223372036854775807
$n = 9223372036854775807;
echo $n; // echoes 9223372036854775807
$n = 9223372036854775808;
echo $n; // echoes 9.2233720368548E+18
Setting precision to something greater, as manniL said, does the trick.
ini_set("precision", 50);
$n = 9223372036854775808;
echo $n; // echoes 9223372036854775808
I have been trying all morning but how would I this number 1304583496 to look like this
13.04583496
and the same goes for this number
456604223 to 4.56604223
There are always 8 numbers to the right.
Divide it with 100000000, or use "pow" function:
$number / pow(10, 8);
You could also use the official number_format method after division to keep your ending zeroes and have your number displayed in a nice manner.
<?php
$num = 1304583496; //the number
echo number_format($num/100000000,8,"."," "); //number of decimals = 8, comma seperator is . and thousands seperator is a space here
?>
For more information on this function: http://www.w3schools.com/php/func_string_number_format.asp
Is there a term for the idea of storing large numbers as letters? For example let's say I have the (relatively small) number 138201162401719 and I want to shrink the number of characters (I know this does not help with saving disk space) to the fewest possible number of characters. There are 26 letters in the English alphabet (but i count them as 25 since we need a zero letter). If I start splitting up my large number into pieces that are each 25 or less I get:
13, 8, 20, 11, 6, 24, 0, 17, 19
If I then count the numbers of the alphabet a=0, b=1, c=2, d=3... I can convert this to:
NIULGYART
So I went from 15 digits long (138201162401719) to 9 characters long (NIULGYART). This could of course be easily converted back to the original number as well.
So...my first question is "Does this have a name" and my second "Does anyone have PHP code that will do the conversion (in both directions)?"
I am looking for proper terminology so that I can do my own research in Google...though working code examples are cool too.
This only possible if you're considering to store your number before processing as a string. Because you can't store huge number as integers. You will lost the precision (13820116240171986468445 will be stored as 1.3820116240172E+22) so the alot of digits are lost.
If you're considering storing the number as a string this will be your answer:
Functions used: intval, chr and preg_match_all.
<?php
$regex = '/(2[0-5])|(1[0-9])|([0-9])/';
$numberString = '138201162401719';
preg_match_all($regex, $numberString, $numberArray, PREG_SET_ORDER);
echo($numberString . " -> ");
foreach($numberArray as $value){
$character = chr (intval($value[0]) + 65);
echo($character);
}
?>
Demo
This is the result:
138201162401719 -> NIULGYART
Here's how I would do it:
Store the big number as a string and split it into an array of numbers containing one digit each
Loop through the array extract 2-digit chunks using substr()
Check if the number is less than 26 (in which case, it is an alphabet) and add them to an array
Use array_map() with chr() to create a new array of characters from the above array
Implode the resulting array to get the cipher
In code:
$str = '138201162401719';
$arr = str_split($str);
$i = 0; // starting from the left
while ($i < count($arr)) {
$n = substr($str, $i, 2);
$firstchar = substr($n, 0, 1);
if ($n < 26 && $firstchar != 0) {
$result[] = substr($str, $i, 2);
$i += 2; // advance two characters
} else {
$result[] = substr($str, $i, 1);
$i++; // advance one character
}
}
$output = array_map(function($n) {
return chr($n+65);
}, $result);
echo implode($output); // => NIULGYART
Demo.
As an alternative, you could convert the input integer to express it in base 26, instead of base 10. Something like (pseudocode):
func convertBase26(num)
if (num < 0)
return "-" & convertBase26(-num) // '&' is concatenate.
else if (num = 0)
return "A"
endif
output = "";
while (num > 0)
output <- ('A' + num MOD 26) & output // Modulus operator.
num <- num DIV 26 // Integer division.
endwhile
return output
endfunc
This uses A = 0, B = 1, up to Z = 25 and standard place notation: 26 = BA. Obviously a base conversion is easily reversible.
strtr() is a magnificent tool for this task! It replaces the longest match as is traverses the string.
Code: (Demo)
function toAlpha ($num) {
return strtr($num, range("A", "Z"));
}
$string = toAlpha("138201162401719");
echo "$string\n";
$string = toAlpha("123456789012345");
echo "$string\n";
$string = toAlpha("101112131415161");
echo "$string\n";
$string = toAlpha("2625242322212019");
echo "$string";
Output:
NIULGYART
MDEFGHIJAMDEF
KLMNOPQB
CGZYXWVUT
Just flip the lookup array to reverse the conversion: https://3v4l.org/YsFZu
Merged: https://3v4l.org/u3NQ5
Of course, I must mention that there is a vulnerability with converting a sequence of letters to numbers and back to letters. Consider BB becomes 11 then is mistaken for eleven which would traslate to L when converted again.
There are ways to mitigate this by adjusting the lookup array, but that may not be necessary/favorable depending on program requirements.
And here is another consideration from CodeReview.
I have been trying to do the same thing in PHP without success.
Assuming I'm using the 26 letters of the English alphabet, starting with A = 0 down to Z as 25:
I find the highest power of 26 lower than the number I am encoding. I divide it by the best power of 26 I found. Of the result I take away the integer, convert it to a letter and multiply the decimals by 26. I keep doing that until I get a whole number. It's ok to get a zero as it's an A, but if it has decimals it must be multiplied.
For 1 billion which is DGEHTYM and it's done in 6 loops obviously. Although my answer demonstrates how to encode, I'm afraid it does not help doing so on PHP which is what I'm trying to do myself. I hope the algorithm helps people out there though.
I'm trying to add thousand separators to a number using PHP and at the same time keep the leading zeros (It's part of the design of an app that the leading 0s stay so that people can see the number grow towards the set target - a 6 figure number).
My initial attempt was to use str_pad to add the leading zeros if the current number calculated was less than 6 figures long. Then to add the commas I used number_format. The obvious issue is that number_format removes the leading 0s.
$num = 550;
$num_padded = str_pad($num, 6, '0', STR_PAD_LEFT);
echo number_format($num_padded);
So that returns 550 instead of 000,550
Does anyone know of a reliable way to achieve the format I'm looking for?
Thanks!
I have in mind this simple trick:
function padAndFormat($number, $length)
{
if(strlen($number)>=$length)
{
return number_format($number);
}
$number = number_format('1'.str_pad($number, $length-1, '0', STR_PAD_LEFT));
$number[0] = '0';
return $number;
}
//var_dump(padAndFormat('517', 6)); //string(7) "000,517"
another way to do this is to use sprintf
// length can be changed, here is 6
implode(',',str_split(sprintf('%06d', $this->iterator),3));
the result will be :
input
result
4
000,004
400
000,400
23560
023,560
1234567
1,234,567
it can be improved by reading the length, and computing automatically the final length, multiple of 3
I don't need number format but I need that comma! :)
<?php
$zeroes=0;
$num = 550;
$num_padded = str_pad($zeroes, 3, '0', STR_PAD_LEFT);
$num_padded = str_pad($num_padded,strlen($num_padded)+strlen($zeroes), ',', STR_PAD_RIGHT);
$num_padded = str_pad($num_padded,strlen($num_padded)+strlen($num), $num, STR_PAD_RIGHT);
echo $num_padded;
OUTPUT :
000,550
One Liner with PHP string manipulation. Works for any number of digits:
function pad($number, $min_digits){
return strrev(implode(",",str_split(str_pad(strrev($number), $min_digits, "0", STR_PAD_RIGHT),3)));
}
/* Output for 9 digits
0,000,001
0,000,012
0,000,123
0,001,234
0,012,345
0,123,456
1,234,567
12,345,678
123,456,789
/**/
How can I separate a number and get the first two digits in PHP?
For example: 1345 -> I want this output=> 13 or 1542 I want 15.
one possibility would be to use substr:
echo substr($mynumber, 0, 2);
EDIT:
please not that, like hakre said, this will break for negative numbers or small numbers with decimal places. his solution is the better one, as he's doing some checks to avoid this.
First of all you need to normalize your number, because not all numbers in PHP consist of digits only. You might be looking for an integer number:
$number = (int) $number;
Problems you can run in here is the range of integer numbers in PHP or rounding issues, see Integers Docs, INF comes to mind as well.
As the number now is an integer, you can use it in string context and extract the first two characters which will be the first two digits if the number is not negative. If the number is negative, the sign needs to be preserved:
$twoDigits = substr($number, 0, $number < 0 ? 3 : 2);
See the Demo.
Shouldn't be too hard? A simple substring should do the trick (you can treat numbers as strings in a loosely typed language like PHP).
See the PHP manual page for the substr() function.
Something like this:
$output = substr($input, 0, 2); //get first two characters (digits)
You can get the string value of your number then get the part you want using
substr.
this should do what you want
$length = 2;
$newstr = substr($string, $lenght);
With strong type-hinting in new version of PHP (> PHP 7.3) you can't use substr on a function if you have integer or float. Yes, you can cast as string but it's not a good solution.
You can divide by some ten factor and recast to int.
$number = 1345;
$mynumber = (int)($number/100);
echo $mynumber;
Display: 13
If you don't want to use substr you can divide your number by 10 until it has 2 digits:
<?php
function foo($i) {
$i = abs((int)$i);
while ($i > 99)
$i = $i / 10;
return $i;
}
will give you first two digits