Python | SymPy Permutation.descents() method

Permutation.descents() : descents() is a sympy Python library function that returns the position of descents in the permutation. Descents are the elements where a[i] > a[i+1]

Syntax : sympy.combinatorics.permutations.Permutation.descents() Return : position of descents in the permutation

Code #1 : descents() Example

Python3 1=1

# Python code explaining
# SymPy.descents()

# importing SymPy libraries
from sympy.combinatorics.partitions import Partition
from sympy.combinatorics.permutations import Permutation

# Using from sympy.combinatorics.permutations.Permutation.descents() method 

# creating Permutation
a = Permutation([[2, 0], [3, 1]])

b = Permutation([1, 3, 5, 4, 2, 0])


print ("Permutation a - descents form : ", a.descents())
print ("Permutation b - descents form : ", b.descents())

Output :

Permutation a - descents form : [1] Permutation b - descents form : [2, 3, 4]

Code #2 : descents() Example - 2D Permutation

Python3 1=1

# Python code explaining
# SymPy.descents()

# importing SymPy libraries
from sympy.combinatorics.partitions import Partition
from sympy.combinatorics.permutations import Permutation

# Using from sympy.combinatorics.permutations.Permutation.descents() method 

# creating Permutation
a = Permutation([[2, 4, 0], 
                 [3, 1, 2],
                 [1, 5, 6]])


print ("Permutation a - descents form : ", a.descents())

Output :

Permutation a - descents form : [0, 3, 5]

Python | SymPy Permutation.descents() method

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