Some examples of the use of * in Python function parameters

List of articles

• • • • • 1. Represents multiple parameters
        • 2. When you call a function , One `*` No, No ` decompression ` parameter list
        • 3. Use one of the function parameters at the same time `*` and `**`

1. Represents multiple parameters

Add before parameter * Number , It means that the number of parameters is more than one , With an asterisk * The parameter passed in by the function of parameter is stored as a tuple （tuple）, Take two * The sign indicates the dictionary （dict）

for example :

def exam0(par0, *par1):
print(par0)
print(par1)
exam1(1,2,3,4)
# 1
# (2,3,4)

def exam1(par0, **par1):
print par0
print par1
exam2(1,a=2,b=3)
# 1
# {a:2, b:3}

2. When you call a function , One * No, No decompression parameter list

def exam3(par0, par1):
print(par0, par1)
args = [1, 2]
exam3(*args)
# 1 2

3. Use one of the function parameters at the same time * and **

def exam4(a, b=10, *args, **kwargs):
print(a)
print(b)
print(args)
print(kwargs)
exam4(1, 2, 3, 4, e=5, f=6, g=7)
# 1
# 2
# 3 4
# {'e': 5, 'g': 7, 'f': 6}