![#Python Membership Operators
Python’s membership operators test for membership in a sequence, such as strings, lists, or
tuples. There are two membership operators as explained below
Operator Description Example
in Evaluates to true if it finds a variable in the specified sequence and false
otherwise.
x in y, here in results in a
1 if x is a member of
sequence y.
not in Evaluates to true if it does not find a variable in the specified sequence and
false otherwise.
x not in y, here not in
results in a 1 if x is not a
member of sequence y.
EXAMPLE CODE
a=[1,2,3,4,5,6,7,8,9,10] # a is a list
print(3 in a) # 3 in list a so result is true
print(20 in a) # 20 not in list a so result is false
print(3 not in a) # 3 not in list a ,(but 3 in list a) so result is false
print(20 not in a) # 20 not in list a ,(but 20 not in list a ) so result is
true
RESULT
True
False
False
True](https://image.slidesharecdn.com/pythonbasicoperators-171005200536/85/Python-basic-operators-17-320.jpg)
Python : basic operators
- 2. Python Basic Operators An operator, in computer programing, is a symbol that usually represents an action or process. #Types of Operator Python language supports the following types of operators. Arithmetic Operators Comparison (Relational) Operators Assignment Operators Logical Operators Bitwise Operators Membership Operators Identity Operators
- 3. #Python Arithmetic Operators Arithmetic operators take numerical values (either literals or variables) as their operands and return a single numerical value. Assume variable a holds 30(a=30) and variable b holds 18(b=18) then Operator Description Example + Addition Adds values on either side of the operator. a + b = 48 - Subtraction Subtracts right hand operand from left hand operand. a – b = 12 * Multiplication Multiplies values on either side of the operator a * b = 540 / Division Divides left hand operand by right hand operand a/b = 1.666 % Modulus Divides left hand operand by right hand operand and returns remainder a% b = 12 ** Exponent Performs exponential (power) calculation on operators a**b =30 to the power 18 // Floor Division - The division of operands where the result is the quotient in which the digits after the decimal point are removed. But if one of the operands is negative, the a//b = 1
- 4. result is floored, i.e., rounded away from zero (towards negative infinity): EXAMPLE CODE a,b=30,18 print('a=',a) print('b=',b) print('na+b=',a+b) print('a-b=',a-b) print('a*b=',a*b) print('a/b=',a/b) print('a%b=',a%b) print('a**b=',a**b) print('a//b=',a//b) RESULT a= 30 b= 18 a+b= 48 a-b= 12 a*b= 540
- 5. a/b= 1.6666666666666667 a%b= 12 a**b= 387420489000000000000000000 a//b= 1 #Python Comparison Operators In computer science, a relational operator is a programming language construct or operator that tests or defines some kind of relation between two entities. relational operators return the integers 0 or 1, where 0 stands for false and 1 stands for true Assume variable a holds 30 and variable b holds 18, Operator Description Example == If the values of two operands are equal, then the condition becomes true. (a == b) is not true. != If values of two operands are not equal, then condition becomes true. a!=b is true > If the value of left operand is greater than the value of right operand, then condition becomes true. (a > b) is true. < If the value of left operand is less than the value of right operand, then condition becomes true. (a < b) is not true.
- 6. >= If the value of left operand is greater than or equal to the value of right operand, then condition becomes true. (a >= b) is true. <= If the value of left operand is less than or equal to the value of right operand, then condition becomes true. (a <= b) is not true. EXAMPLE CODE a,b=30,18 print('a=',a) print('b=',b) print('na>b is ',a>b) print('a<b is',a<b) print('a==b is ',a==b) print('a!=b is',a!=b) print('a<=b is',a<=b) print('a>=b is',a>=b) RESULT a= 30 b= 18 a>b is True a<b is False a==b is False a!=b is True a<=b is False
- 7. a>=b is True #Python Assignment Operators Assume variable a holds 30 and variable b holds 18, and c is a variable Operator Description Example = Assigns values from right side operands to left side operand c = a + b assigns value of a + b into c += Add AND It adds right operand to the left operand and assign the result to left operand c += a is equivalent to c = c + a -= Subtract AND It subtracts right operand from the left operand and assign the result to left operand c -= a is equivalent to c = c - a *= Multiply AND It multiplies right operand with the left operand and assign the result to left operand c *= a is equivalent to c = c * a /= Divide AND It divides left operand with the right operand and assign the result to left operand c /= a is equivalent to c = c / ac /= a is equivalent to c = c / a %= Modulus AND It takes modulus using two operands and assign the result to left operand c %= a is equivalent to c = c % a
- 8. **= Exponent AND Performs exponential (power) calculation on operators and assign value to the left operand c **= a is equivalent to c = c ** a //= Floor Division It performs floor division on operators and assign value to the left operand c //= a is equivalent to c = c // a EXAMPLE CODE a,b=30,18 print('a=',a) print('b=',b) c=a+b print('c=a+b=',c) c+=a #c=c+a c=48+30=78 now c is 78 print('c=c+a=',c) c-=a #c=c-a c=78-30=48 now c is 48 print('c=c-a=',c) c*=a #c=c*a c=48*30=1440 now c is 1440 print('c=c*a=',c) c/=a #c=c/a c=1440/30=48 now c is 48 print('c=c/a=',c) c%=a #c=c%a c=48%30=18 now c is 18 print('c=c%a=',c) c**=a #c=c**a c=18^30=4.551715960790334e+37 now c is 4.551715960790334e+37 print('c=c^a=',c) c//=a #c=c//a c=4.551715960790334e+37//30=1.517238653596778e+3 6 now c is 1.517238653596778e+36 print('c=c//a',c)
- 9. RESULT a= 30 b= 18 c=a+b= 48 c=c+a= 78 c=c-a= 48 c=c*a= 1440 c=c/a= 48.0 c=c%a= 18.0 c=c^a= 4.551715960790334e+37 c=c//a 1.517238653596778e+36 #Python Bitwise Operators Bitwise operator works on bits and performs bit by bit operation.
- 10. At first discuss about AND , OR , XOR AND NOR gate little bit
- 11. 27 26 22 24 23 22 21 20 128 64 32 16 8 4 2 1 ………………………………………………………………………………………………… 0 0 1 1 1 1 0 0 60 0 0 0 0 1 1 0 1 13 Assume if a = 60; and b = 13; Now in binary format they will be as follows a=0011 1100 b=0000 1101 | Binary OR a | b Does a "bitwise or". Each bit of the output is 0 if the corresponding bit of a AND of b is 0, otherwise it's 1. a 0 0 1 1 1 1 0 0 or | b 0 0 0 0 1 1 0 1 Decimal …………………………………………………………………………………………………………. 0 0 1 1 1 1 0 1 61
- 12. & Binary AND a & b Does a "bitwise and". Each bit of the output is 1 if the corresponding bit of a AND of b is 1, otherwise it's 0. a 0 0 1 1 1 1 0 0 and & b 0 0 0 0 1 1 0 1 ………………………………………………………………………………………………………… 0 0 0 0 1 1 0 0 12 ^ Binary XOR x ^ y Does a "bitwise exclusive or". Each bit of the output is the same as the corresponding bit in x if that bit in y is 0, and it's the complement of the bit in x if that bit in y is 1. a 0 0 1 1 1 1 0 0 xor ^ b 0 0 0 0 1 1 0 1 …………………………………………………………………………………………………………
- 13. 0 0 1 1 0 0 0 1 49 ~ Binary Ones Complement ~ a Returns the complement of x - the number you get by switching each 1 for a 0 and each 0 for a 1. This is the same as -a - 1. a 0 0 1 1 1 1 0 0 Ones Complement ~ ……………………………………………………………………………………………………….. 1 1 0 0 0 0 1 1 -61 1 1 0 0 0 0 1 1 -(64-0-0- 0-0-2)-1=64-2-1=-61 Sign bit (1=- or 0=+) << Binary Left Shift a << 2 Returns a with the bits shifted to the left by 2 places (and new bits on the right-hand- side are zeros). a<<2 0 0 1 1 1 1 0 0<<2 1 1 1 1 0 0 0 0 240 >> Binary Right Shift a >> 2 Returns a with the bits shifted to the right by 2 places (and new bits on the left-hand- side are zeros).
- 14. a>>2 0 0 1 1 1 1 0 0>> 0 0 0 0 1 1 1 1 15 Operator Description Example & Binary AND Operator copies a bit to the result if it exists in both operands (a & b) (means 0000 1100) | Binary OR It copies a bit if it exists in either operand. (a | b) = 61 (means 0011 1101) ^ Binary XOR It copies the bit if it is set in one operand but not both. (a ^ b) = 49 (means 0011 0001) ~ Binary Ones Complement It is unary and has the effect of 'flipping' bits. (~a ) = -61 (means 1100 0011 in 2's complement form due to a signed binary number. << Binary Left Shift The left operands value is moved left by the number of bits specified by the right operand. a << 2 = 240 (means 1111 0000) >> Binary Right Shift The left operands value is moved right by the number of bits specified by the right operand. a >> 2 = 15 (means 0000 1111)
- 15. EXAMPLE CODE a=0b00111100 b=0b00001101 print('a=',bin(a),'b=',bin(b)) print('a or b is=',bin(a|b)) print('a and b is=',bin(a&b)) print('a xor b is=',bin(a^b)) print('Ones Complement of a=',bin(~a)) print('a Left Shift by 2 is',bin(a<<2)) print('a Right Shift by 2 is',bin(a>>2)) RESULT a= 0b111100 b= 0b1101 a or b is= 0b111101 a and b is= 0b1100 a xor b is= 0b110001 Ones Complement of a= -0b111101 a Left Shift by 2 is 0b11110000 a Right Shift by 2 is 0b1111
- 16. #Python Logical Operators here are following logical operators supported by Python language. Assume variable a holds 10 and variable b holds 20 then Operator Description Example and Logical AND If both the operands are true then condition becomes true. (a and b) is true. or Logical OR If any of the two operands are non-zero then condition becomes true. (a or b) is true. not Logical NOT Used to reverse the logical state of its operand. Not(a and b) is false. EXAMPLE CODE a,b=10,20 c=c=(a>11)and (b>10) # 0 and 1 so result is false print(c) c=(a>11)or(b>10) # 0 or 1 so result is true print(c) a,b=10,20 c=not((a>11)and (b>10)) # not(0 and 1)=not(false) so result is true print(c) RESULT False True True
- 17. #Python Membership Operators Python’s membership operators test for membership in a sequence, such as strings, lists, or tuples. There are two membership operators as explained below Operator Description Example in Evaluates to true if it finds a variable in the specified sequence and false otherwise. x in y, here in results in a 1 if x is a member of sequence y. not in Evaluates to true if it does not find a variable in the specified sequence and false otherwise. x not in y, here not in results in a 1 if x is not a member of sequence y. EXAMPLE CODE a=[1,2,3,4,5,6,7,8,9,10] # a is a list print(3 in a) # 3 in list a so result is true print(20 in a) # 20 not in list a so result is false print(3 not in a) # 3 not in list a ,(but 3 in list a) so result is false print(20 not in a) # 20 not in list a ,(but 20 not in list a ) so result is true RESULT True False False True
- 18. #Python Identity Operators dentity operators compare the memory locations of two objects. There are two Identity operators as explained below Operator Description Example is Evaluates to true if the variables on either side of the operator point to the same object and false otherwise. x is y, here is results in 1 if id(x) equals id(y). is not Evaluates to false if the variables on either side of the operator point to the same object and true otherwise. x is not y, here is not results in 1 if id(x) is not equal to id(y). EXAMPLE CODE a,b=10,100 print(a is b) print(a is not b) RESULT False True
- 19. ALL Python Operators Precedence Operator Description ** Exponentiation (raise to the power) ~ + - Complement, unary plus and minus (method names for the last two are +@ and -@) * / % // Multiply, divide, modulo and floor division + - Addition and subtraction >> << Right and left bitwise shift & Bitwise 'AND' ^ | Bitwise exclusive `OR' and regular `OR' <= < > >= Comparison operators <> == != Equality operators
- 20. Operator Description = %= /= //= -= += *= **= Assignment operators is is not Identity operators in not in Membership operators not or and Logical operators S.M.SALAQUZZAMAN Department of Electrical and Electronic Engineering (EEE) Bangladesh University of Business and Technology (BUBT) Dhaka-1216, Bangladesh. Email:[email protected]