Re: Help: Get the value of pi up to 200+ digits?

Hi - The 'precision' ini value refers, I believe, only to float numbers, not BC_math numbers (which are stored as strings). I believe the bcmath.scale parameter is the one you need. It can be set via ini_set or bcscale() -

        http://php.he.net/manual/en/function.bcscale.php

Perhaps you could tell us *why* you need pi to 200 digits. If it's just for display, I'd simply define it as a string somewhere in your program:

        define('PI_LOOOOOONNNG', '3.1415927...........8468');

However, I would guess that doing math using the BC functions at that precision would be extremely slow. Going to a dedicated math package like MATLAB or Mathematica or something might be more appropriate.

        steve

At 08:57 AM 9/1/2005, Wong HoWang wrote:

Dear Jordan, I know what you mean. But you may try this one and you will know: <?php ini_set('precision',200); echo pi(); ?> the result is the same as 16!!! So that's why I ask this question! I am not stupid like that! Please help, thx! "Jordan Miller" <jmil@hymiegladstone.com> wrote:534D8D52-751D-45B6-9B49-DD9FA136C727@hymiegladstone.com... http://us3.php.net/manual/en/ini.core.php#ini.precision precision sets the number of significant digits, *NOT* the number of digits displayed after the decimal point. If you want to get pi out to 16 decimal places you need a precision of *17* because the beginning 3 is a significant digit. Your code does exactly this, displaying pi with 15 decimal places. Jordan On Sep 1, 2005, at 8:06 AM, Wong HoWang wrote:

Dear all, I'm trying to do like this but failed: <?php ini_set('precision',16); echo pi(); ?> How can I get more digits after . ? Can anyone help? Thx!

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| Steve Edberg                                      sbedberg@ucdavis.edu |
| Database/Programming/SysAdmin                            (530)754-9127 |
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