nl_tokens: CDF // FUNCTION : cdf ( x sigma ) Evaluates the cumulative distribution function ( CDF ) for a Rayleigh distribution with scale parameter sigma at a value x .
pl_tokens: <mask> cdf ( x , sigma ) { if ( x < 0 ) { return 0 ; } var s2 = pow ( sigma , 2 ) ; return - expm1 ( - pow ( x , 2 ) / ( 2 * s2 ) ) ; }