question: public double length ( ) { return Math . sqrt ( NumberConversions . square ( x ) + NumberConversions . square ( y ) + NumberConversions . square ( z ) ) ; }
target:  Gets the magnitude of the location, defined as sqrt(x^2+y^2+z^2). The value of this method is not cached and uses a costly square-root function, so do not repeatedly call this method to get the location's magnitude. NaN will be returned if the inner result of the sqrt() function overflows, which will be caused if the length is too long. Not world-aware and orientation independent.