nl_tokens: PDF // FUNCTION : pdf ( x mu sigma ) Evaluates the probability density function ( PDF ) for a Normal distribution with mean mu and standard deviation sigma at a value x .
pl_tokens: function pdf ( x , mu , sigma ) { if ( sigma === 0 ) { return x === mu ? Number . POSITIVE_INFINITY : 0 ; } <mask> s2 = pow ( sigma , 2 ) , A = 1 / ( sqrt ( 2 * s2 * PI ) ) , B = - 1 / ( 2 * s2 ) ; return A * exp ( B * pow ( x - mu , 2 ) ) ; }