SymPy | Python中的 Permutation.rank()

Permutation.rank() : rank()是一个 sympy Python库函数，它返回排列的字典排序。

Syntax : sympy.combinatorics.permutations.Permutation.rank()

Return : lexicographic rank of the permutation

代码 #1：rank() 示例

# Python code explaining
# SymPy.Permutation.rank()
  
# importing SymPy libraries
from sympy.combinatorics.partitions import Partition
from sympy.combinatorics.permutations import Permutation
  
# Using from sympy.combinatorics.permutations.Permutation.rank() method 
  
# creating Permutation
a = Permutation([[2, 0], [3, 1]])
  
b = Permutation([1, 3, 5, 4, 2, 0])
  
  
print ("Permutation a - rank form : ", a.rank())
print ("Permutation b - rank form : ", b.rank())

输出 ：

Permutation a – rank form : 16
Permutation b – rank form : 191

代码 #2 : rank() 示例– 2D 排列

# Python code explaining
# SymPy.Permutation.rank()
  
# importing SymPy libraries
from sympy.combinatorics.partitions import Partition
from sympy.combinatorics.permutations import Permutation
  
# Using from sympy.combinatorics.permutations.Permutation.rank() method 
  
# creating Permutation
a = Permutation([[2, 4, 0], 
                 [3, 1, 2],
                 [1, 5, 6]])
  
  
print ("Permutation a - rank form : ", a.rank())

输出 ：

Permutation a – rank form : 2461