generate a random string with with exactly 6 digits (show first 0) - php

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)));

Related

How to cut decimal number using PHP

I have a code where I got some numbers like this:
92.682926829268
I'd like to cut them like this:
92.68
This is my code:
<td><?php if (($row['TotalMatch']) > 10){ echo ($row['OK_05'] / $row['TotalMatch']) * 100; } ?></td>
I tried with floor and round but I get that example I showed at the beginning of post ( 92.682926829268 instead of 92.68 )
Thanks for your attention
Regards!
EDIT Could you give me an example with my code? Thanks
Use sprintf() to format the number.
echo sprintf("%.2f", 92.682926829268);
Example:
https://3v4l.org/U87T9
The expression you're trying to format is this:
($row['OK_05'] / $row['TotalMatch']) * 100
So whichever function you decide to use needs to go around that expression.
As to which function to use, you need to select one that returns a string, not a float.
If you use round, and your expression returns a float that rounds to a number with two zeros after the decimal point, the trailing zeros will not be displayed in the result. For example, echo round(92.0006829268, 2) will display 92, not 92.00. So don't use round if you need to be sure that two decimal places are always displayed. round is a math function, not a formatting function.
floor is really not useful at all here, as it returns a number with no decimal places.
A simple way is to use sprintf as shown in some of the other answers.
echo sprintf("%.2f", ($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.
You can use the round function
$var = 92.682926829268;
$var = round($var, 2)
Or use sprintf (%.2f cuts the number)
$var = sprintf("%.2f", $var);
Try using sprintf like below:
<?php
$mynumber = 98.343434;
echo sprintf('%.2f', $mynumber); // this will output 98.34
You could use bcdiv()
bcdiv($row['OK_05'], ($row['TotalMatch'] * 100), 2);

Always round up on first decimal

I want my variable's first decimal to always be rounded up. For example:
9.66 goes to 9.7
9.55 goes to 9.6
9.51 goes to 9.6
9.00000001 goes to 9.1
How do I do this?
Use round() with an optional precision and round type arguments, e.g.:
round($value, 1, PHP_ROUND_HALF_UP)
The optional second argument to round() is the precision argument and it specifies the number of decimal digits to round to. The third optional argument specifies the rounding mode. See the PHP manual for round for details.
Using round() does not always round up, even when using PHP_ROUND_HALF_UP (e.g. 9.00001 is not rounded to 9.1). You could instead try to use multiplication, ceil() and division:
ceil($value * 10.0) / 10.0
Since these are floating-point values, you might not get exact results.
I made couple tests and suggest the following answer with test cases
<?php
echo '9.66 (expected 9.7) => '.myRound(9.66).PHP_EOL;
echo '9.55 (expected 9.6) => '.myRound(9.55).PHP_EOL;
echo '9.51 (expected 9.6) => '.myRound(9.51).PHP_EOL;
echo '9.00000001 (expected 9.1) => '.myRound(9.00000001).PHP_EOL;
echo '9.9 (expected ??) => '.myRound(9.9).PHP_EOL;
echo '9.91 (expected ??) => '.myRound(9.91).PHP_EOL;
function myRound($value)
{
return ceil($value*10)/10;
}
I'm not a php programmer so will have to answer in "steps". The problem you have is the edge case where you have a number with exactly one decimal. (e.g. 9.5)
Here's how you could do it:
Multiply your number by 10.
If that's an integer, then return the original number (that's the edge case), else continue as follows:
Add 0.5
Round that in the normal way to an integer (i.e. "a.5" rounds up).
Divide the result by 10.
For step (2), sniffing around the php documentation reveals a function bool is_int ( mixed $var ) to test for an integer.
You will need a custom ceil() function, your requirements cannot be satisfied by the default function or by the round.
Use this: online test
You can use this technique. Just explode the given number / string, get the number which is next value / digit of the .. after getting this you need to increment that value and check if the value is greater than 9 or nor, if then divide that and add the carry to the first portion of the main number.
$var = '9.96';
$ar = explode(".", $var);
$nxt = substr($ar[1], 0, 1) + 1;
if($nxt > 9){
$tmp = (string) $nxt;
$num = floatval(($ar[0] + $tmp[0]).".".$tmp[1]);
}
else
$num = floatval($ar[0].".".$nxt);
var_dump($num); // float(10)

Converting an int that is more than 16 digits long into a string in php

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

Use numbers starting with 0 in a variable in php

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.

How can I separate a number and get the first two digits in PHP?

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

Categories