(self, other)
return d
Computes the precedence distance between two permutations.

        Suppose p and p' represent n jobs. The precedence metric
        counts the number of times a job j is prededed by job i
        in both p and p'. This metric is commutative.

        Examples
        ========

        >>> from sympy.combinatorics.permutations import Permutation
        >>> p = Permutation([2, 0, 4, 3, 1])
        >>> q = Permutation([3, 1, 2, 4, 0])
        >>> p.get_precedence_distance(q)
        7
        >>> q.get_precedence_distance(p)
        7

        See Also
        ========

        get_precedence_matrix, get_adjacency_matrix, get_adjacency_distance
Computes the precedence distance between two permutations.
Computes the precedence distance between two permutations .
def get_precedence_distance(self, other):
        """
        Computes the precedence distance between two permutations.

        Suppose p and p' represent n jobs. The precedence metric
        counts the number of times a job j is prededed by job i
        in both p and p'. This metric is commutative.

        Examples
        ========

        >>> from sympy.combinatorics.permutations import Permutation
        >>> p = Permutation([2, 0, 4, 3, 1])
        >>> q = Permutation([3, 1, 2, 4, 0])
        >>> p.get_precedence_distance(q)
        7
        >>> q.get_precedence_distance(p)
        7

        See Also
        ========

        get_precedence_matrix, get_adjacency_matrix, get_adjacency_distance
        """
        if self.size != other.size:
            raise ValueError("The permutations must be of equal size.")
        self_prec_mat = self.get_precedence_matrix()
        other_prec_mat = other.get_precedence_matrix()
        n_prec = 0
        for i in range(self.size):
            for j in range(self.size):
                if i == j:
                    continue
                if self_prec_mat[i, j] * other_prec_mat[i, j] == 1:
                    n_prec += 1
        d = self.size * (self.size - 1)//2 - n_prec
        return d
def get_precedence_distance ( self , other ) : if self . size != other . size : raise ValueError ( "The permutations must be of equal size." ) self_prec_mat = self . get_precedence_matrix ( ) other_prec_mat = other . get_precedence_matrix ( ) n_prec = 0 for i in range ( self . size ) : for j in range ( self . size ) : if i == j : continue if self_prec_mat [ i , j ] * other_prec_mat [ i , j ] == 1 : n_prec += 1 d = self . size * ( self . size - 1 ) // 2 - n_prec return d