Re: Perfect Squares

From: Date: Tue, 25 May 2004 23:59:21 +0000
Subject: Re: Perfect Squares
References: 1  Groups: php.general 
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Stephen Craton wrote:
I'm in a bit of a pickle. I need to find out if a variable is a perfect square or not, and this needs to test for decimal numbers as well, such as 2.25. The thing is, the only function I've found in PHP is gmp_perfect_square() which isn't supported on my web server, and I don't know how to compile the GMP code into PHP on my windows box. So, how exactly would you go about finding out if something is a perfect square or not?
It's been a while since I studied this in math, so I figured I'd find out the definition of perfect square. What I found: http://en.wikipedia.org/wiki/Perfect_square Neither of those definitions fit what for your example number 2.25. For instance, $sqrt = sqrt($number); if ($sqrt * $sqrt == $number) { //should always be true, except negative values and possibly rounding }

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