21 Comments to “PHP: Problems with Long Integers & Scientific Notation”

1. scultisfalt March 04, 2008 @ 3:45 am

   1 Hello there. Just found your site. Great job! I like it much. look here http://live.com

2. Herve Kabla March 20, 2008 @ 10:38 pm

   2 And what about scanning long integers? %d does not work, and %ll is not recognised!

3. Jetlogs March 20, 2008 @ 10:52 pm

   3 Author Comment If scanning, do you mean through POST and GET? This article is more about output rather than input. Are you going to do computations with those integers? If not, you can just parse them as string.

4. Demolitions May 08, 2008 @ 9:03 pm

   4 I have quite the opposite problem, i fetch from a DB a string, which contains a number in the format “5,69656893892803000000E+14″, and i need to computate them, at least compare them, tried typecasting and various conversions, but PHP always treat them as they don’t have the “E+nn” part. Do you have some advice? (i have already changed ‘,’ in ‘.’ before typecasting)

5. Jetlogs May 09, 2008 @ 9:33 am

   5 Author Comment A simple typecasting to float should work if you wanted to do computations or numeric comparisons. Have you already tried this?: $x = "5.69656893892803000000E+14"; $y = "5.69756893892803000000E+14"; $x_float = (float)$x; $y_float = (float)$y; var_dump($x_float < $y_float); //true var_dump($x_float > $y_float); //false

6. Demolitions May 09, 2008 @ 3:36 pm

   6 yes, typecasting wasn’t working, but i finally found the error, i was thinking that the users who entered the data were not fluorescent monkeys, they seem to cannot enter two numbers in the same format, i changed the insertion form and handled the numbers there, now i have correct numbers in the DB, and PHP computes them correctly XD thank you very much for the advice.

7. cvasilak July 02, 2008 @ 6:00 pm

   7 Thanks a lot, worked like a charm! Regards, Christos

8. jonas April 08, 2009 @ 6:36 pm

   8 > Hope this helps anybody who is experiencing the same problems. Indeed. it saved me a lot of time, Thanks Greetings Jonas

9. Chad October 11, 2009 @ 4:26 am

   9 Related problem! I WANT scientific notation. I am working with some numbers in the 2.08e17 range, and that’s an unacceptable number of digits to show. How do I A) show only the first 5 non-zero digits of a number and B) force scientific notation, if this doesn’t include the decimal point?

10. tahsin hasan November 10, 2009 @ 1:51 pm

    10 nice post, lots of time eaten up this php 5.2.6 bug. thanks for the post.

11. Dennis Decoene January 09, 2010 @ 9:32 pm

    11 Fantastic. I was getting this problem with the twitter api’s next cursor. This saved me a bunch of headaches! Dennis

12. ppp January 28, 2010 @ 8:54 pm

    12 Thanks

13. meraj May 24, 2010 @ 8:04 pm

    13 how do i modify the number_format function to get expected result for 899350102000029210 as well. it output 899350102000029400 instead of 899350102000029210 thanks

14. Sean November 10, 2010 @ 11:47 pm

    14 Same problem here, with PHP and the Twitter API. Thanks for the tip!

15. Trackback: November 12, 2010 @ 12:56 am

    15 Lets discuss Technology!! PHP: Problem with Long Integers… Recently we faced an issue in PHP with long integers. The integer number was converted to decimal number. Here is the sample output: $big_integer = 1202400000; echo $big_integer; //outputs 1.2024E+09  $sample_float = (float)100000; //float echo $sample…

16. chris April 07, 2011 @ 5:03 pm

    16 Hi, Be careful. This seems not work for a very large integer. If you have 18446744073709551615, PHP will convert it to 1.84467440737E+19. But if you try to convert it back to a normal integer using number_format($big_integer, 0, ‘.’, ”), you’ll get 18446744073709551616 (the original + 1).

17. Daniel April 26, 2011 @ 3:18 am

    17 Hey, I’m getting the same type of problem as Chris and meraj. The converted integer formats to a different number than intended. Any idea how to solve this. For example, -9223372036854387285 becomes -9223372036854387712 when I pass it to a function and run number_format on it.

18. mctaco May 28, 2011 @ 5:55 pm

    18 10 thumbs up! was having the problem with Facebook uids! solved

19. Dint June 26, 2011 @ 12:27 am

    19 Same problem as meraj, Chris and Daniel. I enter 84268019035021313 and the result is 84268019035021312. Any idea yet on how to fix this? Thanks in advance!

20. Bauke Regnerus March 19, 2012 @ 8:59 pm

    20 Same problem here with PHP 5.3.10. The integers are converted to wrong scientific notation. So, 5311693811158833914 becomes 5.3116938111588E+18, which actually is 5311693811158834176. Still looking for a solution, maybe downgrading PHP.

21. Mafia Inferno April 04, 2012 @ 8:21 pm

    21 Regarding the display of long integers . . . PHP uses a max of 13 digits after the decimal point when using scientific notation. I use a combination of the bc precision Math functions and a custom function to display numbers with commas. The bc Math functions all use strings instead of integers so are more precise and wont be stored using scientific notation. a number format with commas . .. function commas ($str){ // integer only, remove everything after decimal point $arr = explode(“.”, $str, 1); $str = $arr[0]; // reverse the string so we can split each 3 numbers from RTL $str = strrev($str); $xploded = str_split($str,3); $comma_separated = implode(“,”, $xploded); return strrev($comma_separated); }