I was trying to use printf for formatting but I realized that when I use %d, I can't use 0 for the padding specifier with - alignment. Here is what i'm trying to do:
$a = sprintf("%04d",5);
$b = sprintf("%'1-4d",5);
$c = sprintf("%0-4d",5);
$d = sprintf("%0-4s",5);
var_dump($a);//outputs 0005
var_dump($b);//outputs 5111
var_dump($c);//outputs 5(and 4 spaces) why not 5000?
var_dump($d);//outputs 5000
I think PHP is trying to think for you here.
If you right-pad 5 with four 0 characters, how would you be able to tell the difference between that and 50000? Or between 5 right padded with four 0 characters and 50 right padded with three 0 characters?
I don't have PHP handy to test, but what if you tried to use the format "%'0-4d" to convince it to do what you want?
Related
I am looking for a solution for a smart number formatting in PHP.
For example we have 2 numbers below and we need 4 digits after decimal:
1.12345678
0.00002345678
Using normal number formatting, here are the results:
1.1234 // Looking good
0.0000 // No good
Can we make it keep going until there are 4 non-zero digits? If it can return 0.00002345, perfect!!!
Many thanks!!!
Might be overkill and the pattern could be optimized, but for fun; get optional 0s AND 4 NOT 0s after the .:
preg_match('/\d+\.([0]+)?[^0]{4}/', $num, $match);
echo $match[0];
To round it we can get 5 digits after the 0s and then format it to the length of that -1 (which will round):
preg_match('/\d+\.([0]+?[^0]{5})/', $num, $match);
echo number_format($match[0], strlen($match[1])-1);
For $num = '1234.000023456777'; the result will be 1,234.00002346 and the $matches will contain:
Array
(
[0] => 1234.000023456
[1] => 000023456
)
So this is the code I made to slove this:
$num = 0.00002345678;
$num_as_string = number_format($num,PHP_FLOAT_DIG,'.','');
$zeros = strspn($num_as_string, "0", strpos($num_as_string, ".")+1);
echo number_format($num, (4+$zeros), '.', '');
It converts the float number to a string, checks how many zeros exist after the decimal point and then does a number format with the extra zeros accounted for.
Note that it may break if your float is too big, you can change PHP_FLOAT_DIG to a number larger that may fix that.
I am trying to generate a string with exactly 6 random numbers in it. My current code:
$test = sprintf('%6d', rand(1, 1000000));
With this code I get a string that sometimes has an empty value at the beginning like " 53280". I would want to have it produce "053280" in that case. How to achieve this?
You should add a 0 in your conversion specification to indicate that you want zero-padding:
$test = sprintf('%06d', rand(1, 1000000));
// ^-- here
The conversion specifications are documented on the sprintf manual page.
If you don't want to use sprintf (some dont!), an alternative way to do it would be:
$test = str_pad(mt_rand(1, 999999),6,0,STR_PAD_LEFT);
Example output:
736523
024132
003145
Using mt_rand here because its a better random number function (not perfect, but better than just rand). Also adjusted to 999999 since 1000000 could possibly produce a 7 digit number.
Doing a benchmark of 10000 iterations on the three answers provided (Sean, Mine, Aslan), these are the results in speed:
Sean's Method: 0.005
My Method: 0.006
Aslan's Method: 0.009
So you would be better off going with Sean's method.
You can just replace the empty character with 0.
$test = str_replace(" ", "0", sprintf('%6d', rand(1, 1000000)));
Hi i need to save a 010 number in $number and if i do like this php will remove the starting 0
$number = 010
And echo of this will return 10 how can i make it not to remove the initial 0
BR
Martin
Use it as a String:
$number = '010';
Use str_pad() function.
echo str_pad('10',3,'0',STR_PAD_LEFT)
http://php.net/manual/en/function.str-pad.php
Do remember that numbers starting with 0 can also be treated as octal number notation by the PHP compiler, hence if you want to work with decimal numbers, simply use:
$num = '010';
This way the number is saved, can be stored in the database and manipulated like any other number. (Thx to the fact that PHP is very loosely typed language.)
Another method to use would be:
Save number as $num = 10;
Later while printing the value you can use sprintf, like:
sprintf("%03d", $i);
This will print your number in 3 digit format, hence 0 will be added automatically.
Another method:
<?php
$num = 10;
$zerofill = 3;
echo str_pad($num, $zerofill, "0", STR_PAD_LEFT);
/* Returns the wanted result of '010' */
?>
You can have a look at the various options available to you and make a decision. Each of the method given above will give you a correct output.
This:
$difference = 05-1;
results in
4
same if I do this:
$difference = 05-01;
is there a inbuilt way to subtract while keeping leading zeros? I know I can check to see if the difference has only 1 character or not and if so add a leading zero but was just wondering if there is a default way to get the result back with 0 already in it.
No I dont think PHP will natively keep the leading 0's unless its a float. In PHPs mind 4 is 4 not 04 tho 0.4 is 0.4
So if you need the leading 0 in ints lower the 10 pad it with str_pad():
<?php
$difference = (05-1);
echo str_pad($difference, 2, "0", STR_PAD_LEFT);//04
?>
<?php
$difference = 234;
echo str_pad($difference, 2, "0", STR_PAD_LEFT);//234
?>
If it's just a matter of outputting you can use printf() to add leading zeroes. The following:
<?php
printf("Result: %02d", 04-1);
?>
will output:
Result: 03
the %02d translates to fill with '0' (%0 2d) for 2 spaces (%0 2 d) and format as an integer (%02 d). A lot can be done with printf() to set precision, add leading characters, and use placeholders while outputting text.
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