Create les8_sets.py

Sets

Author: alva922

Diff for: les8_sets.py

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+#https://newdigitals.org/2024/01/23/basic-python-programming/#sets
+#In Python, a Set is an unordered collection of data types that is iterable, mutable and has no duplicate elements. The order of elements in a set is undefined though it may consist of various elements.
+#Set items are unchangeable, but you can remove items and add new items.
+#The values True (False) and 1 (0) are considered the same value in sets, and are treated as duplicates.
+#Set items can be of any data type.
+#The major advantage of using a set, as opposed to a list, is that it has a highly optimized method for checking whether a specific element is contained in the set.
+#Sets are written with curly brackets:
+thisset = {"apple", "banana", "cherry"}
+print(thisset)
+Output:
+{'banana', 'cherry', 'apple'}
+#To determine how many items a set has, use the len() function
+thisset = {"apple", "banana", "cherry"}
+ 
+print(len(thisset))
+ 
+Output:
+3
+#Sets are defined as objects with the data type ‘set’:
+myset = {"apple", "banana", "cherry"}
+print(type(myset))
+Output:
+<class 'set'>
+#It is possible to use the set() constructor to make a set
+thisset = set(("apple", "banana", "cherry")) # note the double round-brackets
+print(thisset)
+Output:
+{'banana', 'cherry', 'apple'}
+#Creating a Set
+# Python program to demonstrate 
+# Creation of Set in Python
+ 
+# Creating a Set
+set1 = set()
+print("Initial blank Set: ")
+print(set1)
+ 
+# Creating a Set with 
+# the use of a String
+set1 = set("GeeksForGeeks")
+print("\nSet with the use of String: ")
+print(set1)
+ 
+# Creating a Set with
+# the use of Constructor
+# (Using object to Store String)
+String = 'GeeksForGeeks'
+set1 = set(String)
+print("\nSet with the use of an Object: " )
+print(set1)
+ 
+# Creating a Set with
+# the use of a List
+set1 = set(["Geeks", "For", "Geeks"])
+print("\nSet with the use of List: ")
+print(set1)
+ 
+# Creating a Set with
+# the use of a tuple
+t=("Geeks","for","Geeks")
+print("\nSet with the use of Tuple: ")
+print(set(t))
+ 
+# Creating a Set with
+# the use of a dictionary
+d={"Geeks":1,"for":2,"Geeks":3}
+print("\nSet with the use of Dictionary: ")
+print(set(d))
+ 
+Output:
+Initial blank Set: 
+set()
+ 
+Set with the use of String: 
+{'k', 'e', 'F', 'r', 'o', 'G', 's'}
+ 
+Set with the use of an Object: 
+{'k', 'e', 'F', 'r', 'o', 'G', 's'}
+ 
+Set with the use of List: 
+{'Geeks', 'For'}
+ 
+Set with the use of Tuple: 
+{'Geeks', 'for'}
+ 
+Set with the use of Dictionary: 
+{'Geeks', 'for'}
+#Python has a set of built-in methods that you can use on sets: add, clear, copy, difference, difference_update, discard, intersection, intersection_update, isdisjoint, isubset, etc.
+#Once a set is created, you cannot change its items, but you can add new items.
+#To add one item to a set use the add() method
+thisset = {"apple", "banana", "cherry"}
+ 
+thisset.add("orange")
+ 
+print(thisset)
+Output:
+{'orange', 'banana', 'cherry', 'apple'}
+#To add items from another set into the current set, use the update() method, e.g. add elements from tropical into thisset
+thisset = {"apple", "banana", "cherry"}
+tropical = {"pineapple", "mango", "papaya"}
+ 
+thisset.update(tropical)
+ 
+print(thisset)
+ 
+Output:
+{'banana', 'cherry', 'mango', 'papaya', 'apple', 'pineapple'}
+#To remove an item in a set, use the remove(), or the discard() method
+thisset = {"apple", "banana", "cherry"}
+ 
+thisset.remove("banana")
+ 
+print(thisset)
+ 
+Output:
+{'cherry', 'apple'}
+#Other options: the clear() method empties the set; the del keyword will delete the set completely
+#Loop through the set, and print the values
+thisset = {"apple", "banana", "cherry"}
+ 
+for x in thisset:
+  print(x)
+banana
+cherry
+apple
+
+#The union() method returns a new set with all items from both sets:
+set1 = {"a", "b" , "c"}
+set2 = {1, 2, 3}
+ 
+set3 = set1.union(set2)
+print(set3)
+Output:
+{1, 2, 3, 'a', 'b', 'c'}
+#The intersection() method will return a new set, that only contains the items that are present in both sets.
+x = {"apple", "banana", "cherry"}
+y = {"google", "microsoft", "apple"}
+ 
+z = x.intersection(y)
+ 
+print(z)
+ 
+Output:
+{'apple'}
+#The symmetric_difference_update() method will keep only the elements that are NOT present in both sets
+x = {"apple", "banana", "cherry"}
+y = {"google", "microsoft", "apple"}
+ 
+x.symmetric_difference_update(y)
+ 
+print(x)
+Output:
+{'banana', 'google', 'microsoft', 'cherry'}