#25751 [Ana->Csd]: pow() function return errors

ID: 25751 Updated by: nlopess@php.net Reported By: dbjm at comcast dot net -Status: Analyzed +Status: Closed Bug Type: Documentation problem Operating System: * PHP Version: Irrelevant New Comment: This bug has been fixed in the documentation's XML sources. Since the online and downloadable versions of the documentation need some time to get updated, we would like to ask you to be a bit patient. Thank you for the report, and for helping us make our documentation better. Previous Comments: ------------------------------------------------------------------------ [2003-10-03 22:07:36] sniper@php.net There are some documentation problems: 1. pow() no longer shows any errors, even if parameters are invalid 2. pow(-1,1.1) produces complex number which PHP does not support. For dbjm at comcast dot net: Look manual for "is_finite()" function. ------------------------------------------------------------------------ [2003-10-03 18:12:12] dbjm at comcast dot net Description: ------------ The pow() function returns incorrect numbers when using a negative number base. This is not a crisis to fix for me - I have worked around it. Thanks for the great work on developing PHP. Sincerely, Dave Reproduce code: --------------- echo "pow(3.125, 3.125) = " . pow(3.125, 3.125). "<br>"; echo "pow(-3.125, 3.125) = " . pow(-3.125, 3.125). "<br>"; echo "pow(3.125, -3.125) = " . pow(3.125, -3.125). "<br>"; echo "pow(-3.125, -3.125) = " . pow(-3.125, -3.125). "<br>"; Expected result: ---------------- When the same calcualtion is made using Visual Basic the results are: 3.125 ^ 3.125 = 35.1889507775869 -3.125 ^ 3.125 = -35.1889507775869 3.125 ^ -3.125 = 2.84180112763389E-02 -3.125 ^ -3.125 = -2.84180112763389E-02 Actual result: -------------- Windows 2000: pow(3.125, 3.125) = 35.1889507776 pow(-3.125, 3.125) = -1.#IND pow(3.125, -3.125) = 0.0284180112763 pow(-3.125, -3.125) = -1.#IND Linux 9: pow(3.125, 3.125) = 35.188950777587 pow(-3.125, 3.125) = NAN pow(3.125, -3.125) = 0.028418011276339 pow(-3.125, -3.125) = NAN ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=25751&edit=1