(self, argindex=1)
Return the first derivative of this function.
Return the first derivative of this function.
Return the first derivative of this function .
def fdiff(self, argindex=1):
        """
        Return the first derivative of this function.
        """
        if argindex == 1:
            x = self.args[0]
            return LambertW(x)/(x*(1 + LambertW(x)))
        else:
            raise ArgumentIndexError(self, argindex)
def fdiff ( self , argindex = 1 ) : if argindex == 1 : x = self . args [ 0 ] return LambertW ( x ) / ( x * ( 1 + LambertW ( x ) ) ) else : raise ArgumentIndexError ( self , argindex )