Python学习——运算符

137 阅读1分钟

(1)算术运算符

加:+                #print(1+2)       3
减:-                #print(1-2)       -1
乘:*                #print(1*2)       2
除:/                #print(1/2)       0.5
整除://             #print(1//2)      0
取余:%              #print(1%2)       1
乘方:**             #print(1**2)      1
括号:(),优先      #print((1+2)*2    9

(2)赋值运算符

等号:=,赋值:将等号右边的变量赋值给等号左边得变量名

单变量赋值:

  a=2
  print(a)
  # 2
  

多变量赋值:

  a,b,c=1,1.5,"hello world!"
  print(a)
  print(b)
  print(c)
  # 1
  # 1.5
  #hello world!
  

多变量相同赋值:

a=b=10
print(a)
print(b)
# 10
# 10

(3)复合赋值运算符:

加法赋值运算符:+=
    a+=b   <===>   a=a+b
减法赋值运算符:-+
    a-=b   <===>   a=a-b
乘法赋值运算符:*=
    a*=b   <===>   a=a*b
除法赋值运算符:/=
    a/=b   <===>   a=a/b
整除赋值运算符://=
    a//=b   <===>   a=a//b
取余赋值运算符:%=
    a%=b   <===>   a=a%b
乘方赋值运算符:**=
    a**=b   <===>   a=a**b
    

(4)比较运算符:

等于:==
大于等于:>=
小于等于:<=
大于:>
小于:<
不等于:!=

  
a=5
b=10
print(a==b) # False
print(a>=b) # False
print(a<=b) # True
print(a>b) # False
print(a<b) # True
print(a!=b) # True

(5)逻辑运算符:

and:返回bool值,全真为真,其余为假
or:返回bool值,全假为假,其余为真
not:返回bool值,not a,若a为真,返回False

a = 1
b = 2
c = 3
print((a < b) and (b < c)) # True
print((a > b) and (b < c)) # False
print((a > b) or (b < c)) # True
print(not (a > b)) # True

数学之间的逻辑运算符:

   a = 0 b = 1 c = 2

    # and运算符,只要有⼀个值为0,则结果为0,否则结果为最后⼀个⾮0数字
    print(a and b) # 0
    print(b and a) # 0
    print(a and c) # 0
    print(c and a) # 0
    print(b and c) # 2
    print(c and b) # 1

    # or运算符,只有所有值为0结果才为0,否则结果为第⼀个⾮0数字
    print(a or b) # 1
    print(a or c) # 2
    print(b or c) # 1