[SOLVED] mmm,

[almightyegg]

I have a formula like ($variable^0.5)/4 but, at the moment it is echoing it out as $variable/4, does PHP not take ^ symbol as powers??

[Barand]

No.

 

Use www.php.net/pow

[almightyegg]

That worked, but now I have found another problem, I need to use this formula with positives and negatives, but it works incorrectly with negatives and shows 'NAN' ??

[Barand]

Worked fine for me

 

<?php
echo pow (4, 0.5);      // --> 2
echo pow (4, -0.5);     // --> 0.5
?>

 

If, on the other hand, you are trying to get pow(-4, 0.5) then it will fall over as you can't get the square root of a negative number (without going into the realm of complex numbers)

[almightyegg]

well, it is a strange thing I want it to do, if the number is positive I want it to calculate out a negative number, which I have done, and if it is already negative, then I want it to calculate out a positive number..

 

So would it be easier to remove the - from it? Also can INT columns take negatives?

[Barand]

Also can INT columns take negatives?

 

As long as it isn't defined as UNSIGNED

[almightyegg]

Ah k, so to remove the - should I use a replace and replace it with nothing?

[corbin]

well, it is a strange thing I want it to do, if the number is positive I want it to calculate out a negative number, which I have done, and if it is already negative, then I want it to calculate out a positive number..

 

So would it be easier to remove the - from it? Also can INT columns take negatives?

 

You could just do something like:

 

if($num < 0) {
//negative
}
elseif($num > 0) {
//positive
}
else {
//0
}

[AndyB]

http://ca.php.net/manual/en/function.abs.php - absolute value

[almightyegg]

well, it is a strange thing I want it to do, if the number is positive I want it to calculate out a negative number, which I have done, and if it is already negative, then I want it to calculate out a positive number..

 

So would it be easier to remove the - from it? Also can INT columns take negatives?

 

You could just do something like:

 

if($num < 0) {
//negative
}
elseif($num > 0) {
//positive
}
else {
//0
}

That's what I've been doing, but the problem wasn't that, it was passing the negative number, as it can't compute it...

 

http://ca.php.net/manual/en/function.abs.php - absolute value

That didn't work... hmm, could I just remove the hyphen - somehow?

[Barand]

As AndyB said

 

$x = -5;

$x = abs($x);

echo $x;

[almightyegg]

I went back to my code, I realised when I tried abs() before I'd put it in completely the wrong place :S oops thanks for the help guys