How can I write not greater-than-or-equal-to in php? Is it >!=?
@Ian P: I've added one for you ;-)
Mike
2010-07-08 15:21:38
I'm not going to upvote you simply because no one should be rewarded for knowing the answer to this question.
Lucas Oman
2010-07-08 16:18:02
@Lucas: haha, fair enough :p
Svish
2010-07-08 16:31:18
It is incredible that an answer to this question would garner that much reputation.
BipedalShark
2010-07-08 17:22:12
Well, not exactly. NaNs are supposed to be unordered.
ninjalj
2010-07-08 18:42:16
@BipedalShark, I am a bit in disbelief myself O.o
Svish
2010-07-08 22:12:43
I used to be against weighted reputation based on question difficulty, but this is just about the greatest example in support of it I've ever seen :)
Michael Mrozek
2010-07-10 17:19:32
+8
A:
"not greater than or equal to" is equivalent to "strictly less than" which you write as <.
If you really wanted to say "not greater than or equal to" you could just write !(a >= b).
Neil Williams
2010-07-08 15:20:13
+9
A:
The best way to write this is
$x = 4;
$y = 6;
if($x < $y) echo "True";
// True
$x = 4;
$y = 6;
if(!($x >= $y)) echo "True";
// True
Lizard
2010-07-08 15:21:16
Perhaps this question is a good candidate for code bowling? (The more code - higher points - is the winner)
Jeff Fohl
2010-07-08 15:23:40
@Jeff Fohl: Good grief, no! We might get a distributed, parallelized, XML-backed, synergistic proactive network architecture (which somehow involves a wooden table, and whose sole purpose is to determine if x < y). There is a site for that, but it's not SO.
Piskvor
2010-07-08 15:27:12
@Jeff Fohl: Does that mean that if my code is not less than or equal to your code, you will win?
Mike
2010-07-08 15:28:48
New definition of mathematical induction - if something holds for 4 and 6, it is true for all integers;)
el.pescado
2010-07-08 19:37:12
+3
A:
Technically, you have asked two different questions - how to write A not greater than B or A equal to B and A not equal to B or A greater than B.
The statement A not greater than B or A equal to B implies:
!(A > B) || A == B
which is a tautology for:
A <= B
And A not equal to B or A greater than B implies:
A != B || A > B
which is a tautology for:
A >= B
The other answers of A < B are representative of the statement A not greater than nor A equal to B.
John Rasch
2010-07-08 15:44:46
+37
A:
Oh, fun. In increasing order of complexity:
- <
- (a - b > 0)
- !(a >= b)
- !(a - b <= 0)
- !((a > b) || (a==b))
- !(a - b < 0) && !(a - b == 0)
- !((a - b < 0) || (a - b == 0)) && !(!(a < b))
- !(a - b < ((a * (1/a)-1) * (b * (1/b)-1))) && !(a - b == (a * (1/a)-1) * (b * (1/b)-1)))
Personally, I would reserve #8 for someone who really annoyed me. ;)
Rab
2010-07-08 16:05:06
I just have to mention that #8 will break on integer values (because of integer division) and non integer values (rounding errors messing with equality).
murgatroid99
2010-07-08 16:40:19
@murgatroid Good point about #8. (+1) I must remember to avoid that issue whenever I use it. Perhaps when adding redundant operations to slow down a process, in those cases where the users are known to be evil.
Rab
2010-07-08 17:33:03
@luiscubal Well yeah but that would be too much like using the "<" operator ... I mean, as long as we're making things more complicated than they need to be, let's stick to it.
Rab
2010-07-08 19:04:21
A:
Take a look at this page: http://www.php.net/manual/en/language.operators.logical.php
It shows interesting things about operators and how to use them... I've highlighted this specific logical operators page because these, in particular, has different behaviors when you use their similars, like "||" and "or".
It's worth to take a look =)
Fabiano
2010-07-08 17:50:50
+1
A:
To prove the disbelievers that less than is different than not greater or equal:
<?
$i = acos(4);
print $i."\n";
print is_nan($i)."\n";
if (4>=$i) {
print "ge\n";
} else {
print "nge\n";
}
if (4<$i) {
print "lt\n";
} else {
print "nlt\n";
}
?>
It outputs this on my system:
$ php5 nan.php
NAN
1
ge
lt
ninjalj
2010-07-08 19:22:39