Is there something that's larger than any numbers in PHP? - php

Question

I need to simulate a ∞ in PHP.
So that min(∞,$number) is always $number.

Answer 1

I suppose that, for integers, you could use PHP_INT_MAX , the following code :
var_dump(PHP_INT_MAX);
Gives this output, on my machine :
int 2147483647
But you have to be careful ; see Integer overflow (quoting) :
If PHP encounters a number beyond the
bounds of the integer type, it will
be interpreted as a float instead.
Also, an operation which results in a
number beyond the bounds of the
integer type will return a float
instead.
And, from the Floating point numbers documentation page :
The size of a float is
platform-dependent, although a maximum
of ~1.8e308 with a precision of
roughly 14 decimal digits is a common
value (the 64 bit IEEE format).
Considering the integer overflow, and depending on your case, using this kind of value might be a better (?) solution...

Answer 2

Use the constant PHP_INT_MAX.
http://php.net/manual/en/language.types.integer.php

Answer 3

You could potentially use the PHP_INT_MAX constant (click for PHP manual docs).
However, you may want to think about whether you really need to use it - it seems like a bit of an odd request.

Answer 4

PHP actually has a predefined constant for "infinity": INF. This isn't true infinity, but is essentially the largest float value possible. On 64-bit systems, the largest float is roughly equal to 1.8e308, so this is considered to be equal to infinity.
$inf = INF;
var_dump(min($inf,PHP_INT_MAX)); // outputs int(9223372036854775807)
var_dump(min($inf,1.79e308)); // outputs float(1.79E+308)
var_dump(min($inf,1.799e308)); // outputs float(INF)
var_dump(min($inf,1.8e308)); // outputs float(INF)
var_dump($inf === 1.8e308); // outputs bool(true)
Note, any number with a value larger than the maximum float value will be cast to INF. So therefore if we do, var_dump($inf === 1e50000);, this will also output true even though the maximum float is less than this.

Answer 5

I suppose, assuming this is an integer, you could use PHP_INT_MAX constant.

Answer 6

min($number, $number + 1) ??

Answer 7

In Perl you can use
$INF = 9**9E9;
which is larger than any value you can store in IEEE floating point numbers. And that really works as intended: any non-infinite number will be smaller than $INF:
$N < $INF
is true for any "normal" number $N.
Maybe you use it in PHP too?

Answer 8

min($number,$number) is always $number (also true for max() of course).

Answer 9

If your only concern is comparison function then yes, you can use array(), it will be always larger then any number
like
echo min(array(), 9999999999999999);
or
if (array() > 9999999999999999) {
echo 'array won';
} else {
echo 'number won';
}