Python中的SymPy Permutation.is_even()

Permutation.is_even() : is_even()是一个sympy Python库函数，用于检查排列组合是否为偶数。

语法 : sympy.combinatorics.permutations.Permutation.is_even()

返回：真 – 如果排列组合是偶数；否则为假

代码 #1 : is_even() 示例

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

输出 :

Permutation a – is_even form : True
Permutation b – is_even form : False

代码 #2 : is_even() 例子 – 二维互换

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