Mastering Objects and Classes in Python

Introduction to Objects and Classes in Python

• Objects consist of related data (value) and functions that manipulate that data (methods).

• In Python, almost everything is an object, including integers, strings, floats, and booleans.

• Dates are part of the datetime module in Python, and creating a new date object involves using the date() function.

• A class is a template from which objects are instantiated, while an object describes a particular instance of that class.

• Creating a custom class involves defining its attributes and methods, and a constructor function called init is used to initialize its instance variables.

• Instance variables are variables attached to an object instance, and can be accessed and modified using dot notation.

• Methods are functions attached to an object that can accept arguments and modify instance variables.

• Immutable objects, such as integers and strings, cannot have their value changed, and new objects are created to represent the result in computations.

• Mutable objects, such as custom classes, can be changed and will affect all variables that reference that object.

• In Python, variables reference objects stored in memory, and assignment changes which object a variable references.

• Objects with no references become inaccessible and are automatically removed from memory by Python.

• The is keyword can be used to check whether two variables reference the same object.Objects and References in Python

• Objects in Python combine data and behavior.

• Classes are used to define our own types of objects.

• Instantiating multiple objects of the same class results in different object instances.

• Even if objects have the same value, they occupy different locations in memory.

• Mutating one object will not affect the other.

• The Ellipse class is used as an example to demonstrate multiple instances and references.

• Using the scale method mutates only the object it is called upon.

• The shown program assigns an Ellipse object to var1 and another to var2, then assigns var2 to var1 and mutates var1's height.

• The output of the shown program is 3 for var1's width and 5 for var1's height.

• Understanding references and object instances is important to avoid unexpected behavior in Python programs.

• The next lecture will focus on creating and manipulating strings in Python.

• The Cordelia presentation template used in the lecture is licensed under CC BY 4.0.

Introduction to Objects and Classes in Python

• Objects consist of related data (value) and functions that manipulate that data (methods).

• In Python, almost everything is an object, including integers, strings, floats, and booleans.

• Dates are part of the datetime module in Python, and creating a new date object involves using the date() function.

• A class is a template from which objects are instantiated, while an object describes a particular instance of that class.

• Creating a custom class involves defining its attributes and methods, and a constructor function called init is used to initialize its instance variables.

• Instance variables are variables attached to an object instance, and can be accessed and modified using dot notation.

• Methods are functions attached to an object that can accept arguments and modify instance variables.

• Immutable objects, such as integers and strings, cannot have their value changed, and new objects are created to represent the result in computations.

• Mutable objects, such as custom classes, can be changed and will affect all variables that reference that object.

• In Python, variables reference objects stored in memory, and assignment changes which object a variable references.

• Objects with no references become inaccessible and are automatically removed from memory by Python.

• The is keyword can be used to check whether two variables reference the same object.Objects and References in Python

• Objects in Python combine data and behavior.

• Classes are used to define our own types of objects.

• Instantiating multiple objects of the same class results in different object instances.

• Even if objects have the same value, they occupy different locations in memory.

• Mutating one object will not affect the other.

• The Ellipse class is used as an example to demonstrate multiple instances and references.

• Using the scale method mutates only the object it is called upon.

• The shown program assigns an Ellipse object to var1 and another to var2, then assigns var2 to var1 and mutates var1's height.

• The output of the shown program is 3 for var1's width and 5 for var1's height.

• Understanding references and object instances is important to avoid unexpected behavior in Python programs.

• The next lecture will focus on creating and manipulating strings in Python.

• The Cordelia presentation template used in the lecture is licensed under CC BY 4.0.

Introduction to Objects and Classes in Python

• Objects consist of related data (value) and functions that manipulate that data (methods).

• In Python, almost everything is an object, including integers, strings, floats, and booleans.

• Dates are part of the datetime module in Python, and creating a new date object involves using the date() function.

• A class is a template from which objects are instantiated, while an object describes a particular instance of that class.

• Creating a custom class involves defining its attributes and methods, and a constructor function called init is used to initialize its instance variables.

• Instance variables are variables attached to an object instance, and can be accessed and modified using dot notation.

• Methods are functions attached to an object that can accept arguments and modify instance variables.

• Immutable objects, such as integers and strings, cannot have their value changed, and new objects are created to represent the result in computations.

• Mutable objects, such as custom classes, can be changed and will affect all variables that reference that object.

• In Python, variables reference objects stored in memory, and assignment changes which object a variable references.

• Objects with no references become inaccessible and are automatically removed from memory by Python.

• The is keyword can be used to check whether two variables reference the same object.Objects and References in Python

• Objects in Python combine data and behavior.

• Classes are used to define our own types of objects.

• Instantiating multiple objects of the same class results in different object instances.

• Even if objects have the same value, they occupy different locations in memory.

• Mutating one object will not affect the other.

• The Ellipse class is used as an example to demonstrate multiple instances and references.

• Using the scale method mutates only the object it is called upon.

• The shown program assigns an Ellipse object to var1 and another to var2, then assigns var2 to var1 and mutates var1's height.

• The output of the shown program is 3 for var1's width and 5 for var1's height.

• Understanding references and object instances is important to avoid unexpected behavior in Python programs.

• The next lecture will focus on creating and manipulating strings in Python.

• The Cordelia presentation template used in the lecture is licensed under CC BY 4.0.