gmp_strval

Description

string gmp_strval ( resource gmpnumber [, int base] )

Convert GMP number to string representation in base base. The default base is 10. Allowed values for the base are from 2 to 36.

例子 1. Converting a GMP number to a string
<?php $a = gmp_init("0x41682179fbf5"); printf("Decimal: %s, 36-based: %s", gmp_strval($a), gmp_strval($a,36)); ?>

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caldwell at utm dot NoSpamPlease dot edu
22-Jul-2001 11:17


Warning: gmp_strval may return a null terminated string (e.g., gmp_strval(gmp_init(8)) has two characters. This is because gmp is built for speed, so uses estimates based on things it can get quickly, like the number of bits in N. So since 8 is a 4 bit number, it will be allocated ceil(log10(2^4))=ceil(4*0.30103....) = 2 characters. The gmp folks feel it is the caller's responsibility (in this case the PHP interface) to check whether or not all the characters were required.  PHP might have done this for us (and may in the future), but for now, you need to check (if it matters to you--it sure did in my program!).

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