Why result is always integer?

Question

I have the weirdest thing in PHP.

I have a function like this:

function Calculate_i_from_IDF($coef, $Tc)
{
    print_r($coef);
    $intensity=$coef[0]+$coef[1]*$Tc+$coef[2]*$Tc^2+$coef[3]*$Tc^3+$coef[4]*$Tc^4;
    echo "intensity=$intensity<P>";
    return $intensity;
}

My Tc=1. The result is:

Array ( [0] => 1.1413387743 [1] => -0.7177898193 [2] => 0.6190050656 [3] => -0.4272211298 [4] => 0.0813729821 )

intensity=7

What I don't understand is why $intensity is 7 instead of the expected 0.696706. It is so weird! Any help is greatly appreciated.

Thank you,

Frank

possible duplicate of [Php, calculating exponent with carrot (^) fails](http://stackoverflow.com/questions/14371386/php-calculating-exponent-with-carrot-fails) — Reinstate Monica -- notmaynard, Jan 18 '15 at 03:25

score 1 · Accepted Answer · edited May 23 '17 at 10:25

1

^ is not the exponent operator, but a bitwise operator. That is likely causing the expression to result in an integer. Try using pow.

Related: Php, calculating exponent with carrot (^) fails

edited May 23 '17 at 10:25

Community

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answered Jan 18 '15 at 03:22

Mitch

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Wow. It is that simple! Thank you so much! You saved my day. – Frank Jan 18 '15 at 03:26
1

@Frank, I'm glad to hear it. If that solved your problem, you can accept it as an answer by clicking the green checkmark. See http://meta.stackexchange.com/questions/5234/how-does-accepting-an-answer-work – Mitch Jan 18 '15 at 03:30
Frank . please accept it as an answer. So many people get the answer/help they're looking for and fail to acknowledge the individual who helped them. – terary Jan 18 '15 at 03:35

Why result is always integer?

1 Answers1