Python3 operator (8) and python3 Operator
What is an operator?
A simple example4 + 5 = 9. In the example,4And5CalledOperands,"+"Is called an operator.
Python supports the following types of operators:
1. Arithmetic Operators
Assume that variable a is 10 and variable B is 20:
Example:
1 #! /Usr/bin/python3 2 3 a = 21 4 B = 10 5 c = 0 6 7 c = a + B 8 print ("1-c value :", c) 9 10 c = a-b11 print ("2-c value:", c) 12 13 c = a * b14 print ("3-c value: ", c) 15 16 c = a/b17 print (" 4-c value: ", c) 18 19 c = a % b20 print ("5-c value:", c) 21 22 # modify variables a, B, c23 a = 224 B = 325 c = a ** B 26 print ("6-c value:", c) 27 28 a = 1029 B = 530 c = a // B 31 print ("7-c value:", c)
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Output result:
1 1-c value: 312 2-c value: 113 3-c value: 2104 4-c value: 2.15 5-c value: 16 6-c: 87 7-c: 2
View Code2. comparison operator
Assume that variable a is 10 and variable B is 20:
Example:
1 #! /Usr/bin/python3 2 3 a = 21 4 B = 10 5 c = 0 6 7 if (a = B): 8 print ("1-a = B ") 9 else: 10 print ("1-a is not equal to B") 11 12 if (! = B): 13 print ("2-a is not equal to B") 14 else: 15 print ("2-a is equal to B") 16 17 if (a <B ): 18 print ("3-a less than B") 19 else: 20 print ("3-a greater than or equal to B") 21 22 if (a> B ): 23 print ("4-a greater than B") 24 else: 25 print ("4-a less than or equal to B ") 26 27 # modify the values of variables a and B 28 a = 5; 29 B = 20; 30 if (a <= B ): 31 print ("5-a less than or equal to B") 32 else: 33 print ("5-a greater than B") 34 35 if (B> = ): 36 print ("6-B greater than or equal to a") 37 else: 38 print ("6-B less than ")
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Output result of the above instance:
1 1-a is not equal to b2 2-a is not equal to b3 3-a is greater than or equal to b4 4-a is greater than b5 5-a is less than or equal to b6 6-B is greater than or equal to
View Code3. value assignment operator
Example:
1 #! /Usr/bin/python3 2 3 a = 21 4 B = 10 5 c = 0 6 7 c = a + B 8 print ("1-c value :", c) 9 10 c + = a11 print ("2-c value:", c) 12 13 c * = a14 print ("3-c value :", c) 15 16 c/= a 17 print ("4-c value:", c) 18 19 c = 220 c % = a21 print ("5-c value:", c) 22 23 c ** = a24 print ("6-c value: ", c) 25 26 c // = a27 print (" 7-c value: ", c)
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Output result of the above instance:
1 1-c value: 312 2-c value: 523 3-c value: 10924 4-c value: 52.05 5-c value: 26 6-c: 20971527 7-c: 99864
View Code 4. bitwise operators
Bitwise operators regard numbers as binary values for calculation.
The binary format of variable a is 60 and variable B is 13 in the following table:
1 a = 0011 1100 2 3 b = 0000 1101 4 5 ----------------- 6 7 a&b = 0000 1100 8 9 a|b = 0011 110110 11 a^b = 0011 000112 13 ~a = 1100 0011
Example:
1 #! /Usr/bin/python3 2 3 a = 60 #60 = 0011 1100 4 B = 13 #13 = 0000 1101 5 c = 0 6 7 c = a & B; #12 = 0000 1100 8 print ("1-c:", c) 9 10 c = a | B; #61 = 0011 1101 11 print ("2-c:", c) 12 13 c = a ^ B; #49 = 0011 000114 print ("3-c:", c) 15 16 c = ~ A; #-61 = 1100 001117 print ("4-c value:", c) 18 19 c = a <2; #240 = 1111 000020 print ("5-c:", c) 21 22 c = a> 2; #15 = 0000 111123 print ("6-c value:", c)
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Output result of the above instance:
1 1-c value: 122 2-c value: 613 3-c value: 494 4-c value: -615 5-c: 2406 6-c: 15
View Code5. logical operators
Example:
1 #! /Usr/bin/python3 2 3 a = 10 4 B = 20 5 6 if (a and B): 7 print ("1-variables a and B are both true ") 8 else: 9 print ("1-variables a and B have a not true") 10 11 if (a or B ): 12 print ("2-variables a and B are both true, or one of the variables is true") 13 else: 14 print ("2-variables a and B are not true ") 15 16 # modify the value of variable a 17 a = 018 if (a and B): 19 print ("3-variables a and B are both true") 20 else: 21 print ("3-variables a and B have a not true") 22 23 if (a or B): 24 print ("4-variables a and B are both true, or one of the variables is true ") 25 else: 26 print (" 4-variables a and B are not true ") 27 28 if not (a and B ): 29 print ("5-variables a and B are both false, or one of the variables is false") 30 else: 31 print ("5-variables a and B are both true ")
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Output result of the above instance:
1 1-variables a and B are both true2 2-variables a and B are both true, or if one of the variables is true3 3-variables a and B, either of them is true if they are not true4 4-variables a and B, or one of the variables is true5-variables a and B are both false, or one of the variables is false.
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6. member operators
In addition to the preceding operators, Python also supports member operators. The test instance contains a series of members, including strings, lists, and tuples.
Example:
1 #! /Usr/bin/python3 2 3 a = 10 4 B = 20 5 list = [1, 2, 3, 4, 5]; 6 7 if (a in list ): 8 print ("1-variable a in the list given") 9 else: 10 print ("1-variable a is not in the list given ") 11 12 if (B not in list): 13 print ("2-variable B is not in list in the given list") 14 else: 15 print ("2-variable B in the given list") 16 17 # modify the value of variable a 18 a = 219 if (a in list ): 20 print ("3-variable a in the list given") 21 else: 22 print ("3-variable a is not in the list given ")
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Output result of the above instance:
1 1-variable a is not in the given list. list 2 2-variable B is not in the given list. list 3-variable a is in the list of the given list.
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7. Identity Operators
Identity operators are used to compare the storage units of two objects.
Note:The id () function is used to obtain the object memory address.
Example:
1 #! /Usr/bin/python3 2 3 a = 20 4 B = 20 5 6 if (a is B): 7 print ("1-a and B have the same ID ") 8 else: 9 print ("1-a and B do not have the same identifier") 10 11 if (id (a) = id (B )): 12 print ("2-a and B have the same identifier") 13 else: 14 print ("2-a and B do not have the same identifier ") 15 16 # modify the value of variable B 17 B = 3018 if (a is B): 19 print ("3-a and B have the same identifier") 20 else: 21 print ("3-a and B do not have the same identifier") 22 23 if (a is not B): 24 print ("4-a and B do not have the same identifier ") 25 else: 26 print ("4-a and B have the same ID ")
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Output result of the above instance:
1 1-a and B have the same ID 2 2-a and B have the same ID 3 3-a and B do not have the same ID 4-a and B do not have the same ID
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Note: is and = are different
Is used to determine whether two variables reference the same object, = is used to determine whether the value of the referenced variables is equal.
For example:
1 >>>a = [1, 2, 3] 2 >>> b = a 3 >>> b is a 4 True 5 >>> b == a 6 True 7 >>> b = a[:] 8 >>> b is a 9 False10 >>> b == a11 True
8. Operator priority
The following table lists all operators with the highest to lowest priority:
Example:
1 #! /Usr/bin/python3 2 3 a = 20 4 B = 10 5 c = 15 6 d = 5 7 e = 0 8 9 e = (a + B) * c/d #(30*15)/510 print ("(a + B) * c/d:", e) 11 12 e = (a + B) * c)/d #(30*15)/513 print ("(a + B) * c) /d: ", e) 14 15 e = (a + B) * (c/d); # (30) * (15/5) 16 print ("(a + B) * (c/d) Calculation Result:", e) 17 18 e = a + (B * c)/d; #20 + (150/5) 19 print ("a + (B * c)/d:", e)
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Output result of the above instance:
1 (a + B) * c/d Calculation Result: 90.02 (a + B) * c)/d Calculation Result: 90.03 (a + B) * (c/d) Calculation Result: 90.04 a + (B * c)/d Calculation Result: 50.0
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