Python| sympy.primefactors() 方法

在sympy.primefactors()方法的帮助下，我们可以找到给定数字的质因数。与factorint()不同， primefactors()不返回-1或0 。

Syntax: primefactors(n)

Parameter:
n – It denotes an integer.

Returns: Returns a list of prime factors of the given integer.

示例 #1：

# import primefactors() method from sympy
from sympy import primefactors
  
n = 2 * 6*21 * 11
  
# Use primefactors() method 
primefactors_n = primefactors(n) 
      
print("The prime factors of {} : {}".format(n, primefactors_n))

输出：

The prime factors of 2772 : [2, 3, 7, 11]

示例 #2：

# import primefactors() method from sympy
from sympy import primefactors
  
n = -210
  
# Use primefactors() method 
primefactors_n = primefactors(n) 
      
print("The prime factors of {} : {}".format(n, primefactors_n))

输出：

The prime factors of -210 : [2, 3, 5, 7]