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phpnanpow

php pow function returns NAN

When I execute 

echo pow( -0.3741569180353 , 0.2 ) ;

I am getting result NAN

While in excel and calculator, I am getting the answer -0.8215.

What is the solution to fix this as I am having lot of such calculations ?

Solution

  • After some consultation with the experts in Room #11, pow() won't work with the root of a negative number. Should the answer be 0.8215 or -0.8215?

    Quirkily, using the ** (power) operator will work with the root of a negative number

    echo -0.3741569180353 ** 0.2 ;

    because ** has higher precedence than -, so effectively what you're doing is

    echo -(0.3741569180353 ** 0.2) ;