Python| sympy.expand_func() 方法

借助sympy.expand_func()方法，我们可以根据一些数学恒等式扩展特殊函数。

Syntax: expand_func(expression)

Parameter:
expression – It is mathematical expression which is to expanded.

Returns: Returns a mathematical expression corresponding to the input in terms of some mathematical identities.

示例 #1：

# import sympy 
from sympy import * 
  
x = symbols('x')
expr = gamma(x + 3)
print("Expression = {}".format(expr))
   
# Use sympy.expand_func() method 
expand_expr = expand_func(expr)  
      
print("Expanded Expression : {}".format(expand_expr))  

输出：

Expression = gamma(x + 3)
Expanded Expression : x*(x + 1)*(x + 2)*gamma(x)

示例 #2：

# import sympy 
from sympy import * 
  
x = symbols('x')
expr = binomial(x, 3)
print("Expression = {}".format(expr))
   
# Use sympy.expand_func() method 
expand_expr = expand_func(expr)  
      
print("Expanded Expression : {}".format(expand_expr))  

输出：

Expression = binomial(x, 3)
Expanded Expression : x*(x - 2)*(x - 1)/6