How to install GMP extension for PHP
To install GMP for PHP7.0 on Ubuntu, run: sudo apt-get install php7.0-gmp Make sure your php.ini contains the following: extension=php_gmp.so To find out where your php.ini is located, run: php –ini
gmp
In PHP, how do I generate a big pseudo-random number?
Try the following: function BigRandomNumber($min, $max) { $difference = bcadd(bcsub($max,$min),1); $rand_percent = bcdiv(mt_rand(), mt_getrandmax(), 8); // 0 – 1.0 return bcadd($min, bcmul($difference, $rand_percent, 8), 0); } The math is as following: multiply the difference between the minimum and maximum by a random percentage, and add to the minimum (with rounding to an int).
How are extremely large floating-point numbers represented in memory?
Current computers have 32 or 64-bit registers, so doing calculations on bytes is very inefficient. Also, computers work in binary, so using a base that is a power of 2 is more efficient. They’ll use base 232 or 264 like Mysticial said. Each computer word will store a digit of the number and they work … Read more
What are the best (portable) cross-platform arbitrary-precision math libraries? [closed]
GMP is the popular choice. Squeak Smalltalk has a very nice library, but it’s written in Smalltalk. You asked for relevant books or articles. The tricky part of bignums is long division. I recommend Per Brinch Hansen’s paper Multiple-Length Division Revisited: A Tour of the Minefield.
How to install GCC piece by piece with GMP, MPFR, MPC, ELF, without shared libraries?
The Easy Way If you’re a typical developer, you can install the easy way, using instructions at http://gcc.gnu.org/wiki/InstallingGCC or your system package manager such as: apt install gcc # for Debian, Ubuntu, etc. yum install gcc # for RedHat, CentOS, etc. brew install gcc # for Mac OS X The Hard Way GCC says the … Read more