Lua vs. Python: What Are the Differences?

Lua vs. Python: What Are the Differences?
Adnene Mabrouk
Technical writer
Python Lua
06.05.2024
Reading time: 5 min

Python and Lua stand out as two versatile programming languages, each with its own strengths and ideal use cases. Python, renowned for its readability and extensive libraries, appeals to a wide range of developers, while Lua’s lightweight design and flexibility make it more popular for embedded systems and game development. 

Despite their differences, both languages offer rapid development cycles, dynamic typing and vibrant communities, making them valuable tools for various projects and programming tasks.

  • Lua programming language

    • Lightweight and Embeddable: Lua is a lightweight, embeddable scripting language.

    • Procedural, Object-Oriented, and Functional: It supports procedural, object-oriented, and functional programming paradigms.

    • Used for Configuration and Scripting: Lua finds applications in configuration, scripting, and rapid prototyping.

  • Python programming language

    • Interpreted and Object-Oriented: Python is an interpreted, portable, interactive, and object-oriented language.

    • Modules and Exceptions: It boasts modules, exceptions, dynamic typing, and very high-level dynamic data types.

What Is Lua?

  • What is Lua used for:

    • Lua is usually used in embedded applications and games.

    • Major games like World of Warcraft and Angry Birds use Lua as a scripting language.

    • It was also used in the Torch machine learning library (although PyTorch has now taken over).

  • Learning Lua language:

    • Lua is relatively simple to learn, with features like meta-mechanisms and coroutines.

    • Beginners can start learning Lua code using online demos and tutorials. You can create simple Lua commands as in the examples below.

What Is Python?

  • What is Python used for:

    • Python is widely applicable and used for various purposes.

    • It excels in web development, data analysis, scientific computing, and machine learning.

    • PyTorch and TensorFlow (both Python-based) dominate the machine learning and deep learning landscape.

  • Learning Curve:

    • Python is beginner-friendly, but its extensive ecosystem can be overwhelming initially.

    • Resources like tutorials, documentation, and online courses make learning Python accessible.

Syntax and Language Features Comparison

  • Lua:

    • Lua code is simple and has procedural syntax.

    • Data description based on associative (key-value) arrays.

    • Extensible semantics.

  • Python:

    • Clear, readable syntax (often called “executable pseudocode”).

    • Rich standard library.

    • Supports list comprehensions, generators, and decorators.

Lua Programming Tutorial

These are some examples of how to program in Lua:

Hello, World!

print("Hello, World!")

Table iteration :

fruits = {"apple", "banana", "orange"}
for key, value in ipairs(fruits) do
  print(value)
end

Function definition :

function greet(name)
  print("Hello, " .. name .. "!")
end
greet("Alice")

Python Programming Tutorial

These are some examples of how to program in Python:

Hello, World!

print("Hello, World!")

Table iteration :

fruits = ["apple", "banana", "orange"]
for fruit in fruits:
  print(fruit)

Function definition :

def greet(name):
  print("Hello, " + name + "!")
greet("Bob")

Performance and Speed

  • Lua code:

    • Lightweight and efficient.

    • Well-suited for embedded systems and real-time applications.

  • Python code:

    • Slower than Lua due to its high-level abstractions.

    • However, Python’s performance is often sufficient for most applications.

Use Cases and Applications

  • Lua code:

    • Video games (e.g., Unity game engine).

    • Embedded systems.

    • Scripting in applications like Adobe Lightroom.

  • Python code:

    • Web development.

    • Data science and analytics.

    • Automation and scripting.

    • Machine learning and artificial intelligence.

Ecosystem and Libraries

  • Lua coding language:

    • Smaller ecosystem compared to Python.

    • Focused on specific domains (e.g., game development).

  • Python coding language:

    • Vast ecosystem with libraries for almost every imaginable task.

    • Popular libraries: NumPy, Pandas, Django, and more.

Community and Support

  • Lua:

    • Smaller community but active in specific niches.

    • Documentation and community forums available. Multiple Lua tutorials can be found online as well.

  • Python:

    • Large, vibrant community.

    • Abundant resources, tutorials, and Stack Overflow discussions.

Conclusion

  • Choose Lua If:

    • You need a lightweight, embeddable language.

    • Your project involves game development or embedded systems.

  • Choose Python If:

    • You seek versatility, readability, and a broad ecosystem.

    • Your focus includes web development, data science, or machine learning.

In summary, Lua and Python are both powerful programming languages with their own strengths and use cases. Lua excels in simplicity, efficiency, and integration, making it ideal for embedded systems and game development. Python, on the other hand, offers versatility, readability, and a vast ecosystem of libraries, making it suitable for a wide range of applications including web development, data analysis, and artificial intelligence. The choice between Lua and Python ultimately depends on the specific requirements and preferences of the project at hand.

Python Lua
06.05.2024
Reading time: 5 min

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15 January 2025 · 6 min to read
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How to Split a String Using the split() Method in Python

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Each occurrence of the delimiter results in a new element in the resulting list, even if the element is empty. data = "one,,two,,,three" items = data.split(',') print(items) Output: ['one', '', 'two', '', '', 'three'] Splitting a String by Multiple Characters There are cases where you need to split a string using multiple delimiters or complex splitting rules. In such cases, it is recommended to use the re module and the re.split() function, which supports regular expressions. import re beverage_data = "coffee;tea juice|soda" beverages = re.split(r'[;|\s]', beverage_data) print(beverages) Output: ['coffee', 'tea', 'juice', 'soda'] In this example, a regular expression is used to split the string by several types of delimiters. Tips for Using the split() Method The split() method is a powerful and flexible tool for working with textual data in Python. 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13 January 2025 · 8 min to read
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How to Convert a List to a Dictionary in Python

Python offers several fundamental data structures for storing data. Among the most popular are: List: Values with indices. Dictionary: Values with keys. Converting data from one type to another is essential to any dynamically typed programming language. Python, of course, is no exception. This guide will explain in detail what lists and dictionaries are and demonstrate various ways to convert one type to another. All examples in this article were executed using the Python interpreter version 3.10.12 on the Ubuntu 22.04 operating system, running on a Hostman cloud server. The list Type A list in Python is an ordered data structure of the "index-value" type. To create a list, use square brackets with values separated by commas: my_list = [False, True, 2, 'three', 4, 5] The list structure can be displayed in the console: print(my_list) The output will look like this: [False, True, 2, 'three', 4, 5] Accessing list values is done via indices: print(my_list[0]) # Output: False print(my_list[1]) # Output: True print(my_list[2]) # Output: 2 print(my_list[3]) # Output: three print(my_list[4]) # Output: 4 print(my_list[5]) # Output: 5 The dict Type A dictionary in Python is an unordered data structure of the "key-value" type. To create a dictionary, use curly braces with keys and values separated by colons and each pair separated by commas: my_dict = { 'James': '357 99 056 050', 'Natalie': '357 96 540 432', 'Kate': '357 96 830 726' } You can display the dictionary structure in the console as follows: print(my_dict) The output will look like this: {'James': '357 99 056 050', 'Natalie': '357 96 540 432', 'Kate': '357 96 830 726'} Accessing dictionary values is done via keys: print(my_dict['James']) # Output: 357 99 056 050 print(my_dict['Natalie']) # Output: 357 96 540 432 print(my_dict['Kate']) # Output: 357 96 830 726 Converting a List to a Dictionary You can convert a list to a dictionary in several ways: Use the dict.fromkeys() function, which creates a new dictionary with keys from the list. Use a dictionary comprehension with auxiliary functions and conditional operators. The latter option provides more flexibility for generating new dictionaries from existing lists. Creating Dictionary Keys from a List Using dict.fromkeys() The simplest way to create a dictionary from a list is to take the elements of a list instance and make them the keys of a dict instance. Optionally, you can add a default value for all keys in the new dictionary. This can be achieved using the standard dict.fromkeys() function. With this method, you can set a default value for all keys but not for individual keys. Here is an example of creating such a dictionary with keys from a list: objects = ['human', 'cat', 'alien', 'car'] # list of objects objects_states = dict.fromkeys(objects, 'angry') # create a dictionary with a default value for all keys objects_states_empty = dict.fromkeys(objects) # create a dictionary without specifying default values print(objects_states) # output the created dictionary with values print(objects_states_empty) # output the created dictionary without values Console output: {'human': 'angry', 'cat': 'angry', 'alien': 'angry', 'car': 'angry'} {'human': None, 'cat': None, 'alien': None, 'car': None} Creating a Dictionary from a List Using Dictionary Comprehension Another way to turn a list into dictionary keys is by using dictionary comprehension. This method is more flexible and allows for greater customization of the new dictionary. In its simplest form, the comprehension iterates over the list and copies all its elements as keys into a new dictionary, assigning them a specified default value. Here’s how to create a dictionary from a list using dictionary comprehension: objects = ['human', 'cat', 'alien', 'car'] objects_states = {obj: 'angry' for obj in objects} # dictionary comprehension with a string as the default value objects_states_empty = {obj: None for obj in objects} # dictionary comprehension with a default value of None print(objects_states) print(objects_states_empty) Console output: {'human': 'angry', 'cat': 'angry', 'alien': 'angry', 'car': 'angry'} {'human': None, 'cat': None, 'alien': None, 'car': None} In Python, the None object is a special value (null in most programming languages) that represents the absence of a value. The None object has a type of NoneType: print(type(None))  # Output: <class 'NoneType'> Creating a Dictionary from a List Using Dictionary Comprehension and the zip() Function A more advanced method is to use two lists to generate a dictionary: one for the keys and the other for their values. For this purpose, Python provides the zip() function, which allows iteration over multiple objects simultaneously. In simple loops, we can use this function like this: objects = ['human', 'cat', 'alien', 'car'] states = ['walking', 'purring', 'hiding', 'driving'] for obj, state in zip(objects, states): print(obj, state) The console output will be: human walking cat purring alien hiding car driving Thanks to this function, dictionary comprehension can simultaneously use elements from one list as keys and elements from another as values. In this case, the syntax for dictionary comprehension is not much different from a simple iteration: objects = ['human', 'cat', 'alien', 'car'] # list of future dictionary keys states = ['walking', 'purring', 'hiding', 'driving'] # list of future dictionary values objects_states = {obj: state for obj, state in zip(objects, states)} # dictionary comprehension iterating over both lists print(objects_states) Console output: {'human': 'walking', 'cat': 'purring', 'alien': 'hiding', 'car': 'driving'} A natural question arises: what happens if one of the lists is shorter than the other? objects = ['human', 'cat', 'alien', 'car'] states = ['walking', 'purring'] objects_states = {obj: state for obj, state in zip(objects, states)} print(objects_states) The output will be: {'human': 'walking', 'cat': 'purring'} Thus, iteration in the dictionary comprehension stops at the shortest list. The code above can be written in a very compact form using the dict() constructor: objects = ['human', 'cat', 'alien', 'car'] states = ['walking', 'purring', 'hiding', 'driving'] objects_states = dict(zip(objects, states)) # create a dictionary from two lists without a for loop print(objects_states) The console output will be the same as in the previous examples: {'human': 'walking', 'cat': 'purring', 'alien': 'hiding', 'car': 'driving'} Creating a Dictionary with zip() and Conditional Logic In real-world applications, logic is often more complex than the simple examples shown earlier. Sometimes, you need to convert lists into dictionaries while applying specific conditions. For instance, some elements might need modification before inclusion in the dictionary or might not be included at all. This can be achieved using conditions in dictionary comprehensions. For example, we can exclude specific elements from the resulting dictionary: objects = ['human', 'cat', 'alien', 'car'] states = ['walking', 'purring', 'hiding', 'driving'] objects_states = {obj: state for obj, state in zip(objects, states) if obj != 'alien'} # Protect Earth from unknown extraterrestrial influence print(objects_states) Console output: {'human': 'walking', 'cat': 'purring', 'car': 'driving'} We can refine the selection criteria further by introducing multiple conditions: objects = ['human', 'cat', 'alien', 'car'] states = ['walking', 'purring', 'hiding', 'driving'] objects_states = {obj: state for obj, state in zip(objects, states) if obj != 'alien' if obj != 'cat'} # Exclude the alien and the cat—who might be a disguised visitor from another galaxy print(objects_states) Console output: {'human': 'walking', 'car': 'driving'} When using multiple if statements in a dictionary comprehension, they behave as if connected by a logical and operator. You can make dictionary generation even more flexible by combining if and else operators: objects = ['human', 'cat', 'alien', 'car'] states = ['walking', 'purring', 'hiding', 'driving'] # In this example, all string elements in the first list are longer than those in the second list, except for 'cat' objects_states = { obj: ('[SUSPICIOUS]' if len(obj) < len(state) else 'calmly ' + state) for obj, state in zip(objects, states) } # Mark the suspicious 'cat' appropriately and slightly modify other values print(objects_states) Console output: {'human': 'calmly walking', 'cat': '[SUSPICIOUS]', 'alien': 'calmly hiding', 'car': 'calmly driving'} Creating a Complex Dictionary from a Single List In the earlier examples, we created dictionaries from two separate lists. But what if the keys and values needed for the new dictionary are contained within a single list? In such cases, the logic of the dictionary comprehension needs to be adjusted: objects_and_states = [ 'human', 'walking', 'cat', 'purring', 'alien', 'hiding', 'car', 'driving' ] # Keys and values are stored sequentially in one list objects_states = { objects_and_states[i]: objects_and_states[i + 1] for i in range(0, len(objects_and_states), 2) } # The `range` function specifies the start, end, and step for iteration: range(START, STOP, STEP) print(objects_states) Console output: {'human': 'walking', 'cat': 'purring', 'alien': 'hiding', 'car': 'driving'} Sometimes, a list might contain nested dictionaries as elements. The values of these nested dictionaries can also be used to create a new dictionary. Here’s how the logic changes in such cases: objects = [ {'name': 'human', 'state': 'walking', 'location': 'street'}, {'name': 'cat', 'state': 'purring', 'location': 'windowsill'}, {'name': 'alien', 'state': 'hiding', 'location': 'spaceship'}, {'name': 'car', 'state': 'driving', 'location': 'highway'} ] objects_states = { obj['name']: obj['state'] for obj in objects } # Extract 'name' as key and 'state' as value print(objects_states) Console output: {'human': 'walking', 'cat': 'purring', 'alien': 'hiding', 'car': 'driving'} This approach enables handling more complex data structures, such as lists of dictionaries, by targeting specific key-value pairs from each nested dictionary. Converting a Dictionary to a List Converting a dictionary into a list in Python is a straightforward task, often better described as extracting data. From a single dictionary, you can derive several types of lists: A list of keys A list of values A list of key-value pairs Here’s how it can be done: objects_states = { 'human': 'walking', 'cat': 'purring', 'alien': 'hiding', 'car': 'driving' } # Convert dictionary components to lists using the `list()` function objects_keys = list(objects_states.keys()) # List of keys objects_values = list(objects_states.values()) # List of values objects_items = list(objects_states.items()) # List of key-value pairs print(objects_keys) print(objects_values) print(objects_items) Console output: ['human', 'cat', 'alien', 'car'] ['walking', 'purring', 'hiding', 'driving'] [('human', 'walking'), ('cat', 'purring'), ('alien', 'hiding'), ('car', 'driving')] Conclusion Lists and dictionaries are fundamental data structures in Python, each offering distinct ways of storing and accessing data. Dictionaries are more informative than lists, storing data as key-value pairs, whereas lists store values that are accessed by index. Converting a dictionary into a list is straightforward, requiring no additional data since you’re simply extracting keys, values, or their pairs. Converting a list into a dictionary, on the other hand, requires additional data or rules to map the list elements to dictionary keys and values. There are a few methods to convert a List to Dictionary Tool Key Values Syntax dict.fromkeys() Common new_dict = dict.fromkeys(old_list) Dictionary Comprehension Common new_dict = {new_key: 'any value' for new_key in old_list} Dict Comp + zip() Unique new_dict = {new_key: old_val for new_key, old_val in zip(list1, list2)} Dict Comp + zip() + if Unique new_dict = {new_key: old_val for new_key, old_val in zip(list1, list2) if ...} Dict Comp + zip() + if-else Unique new_dict = {new_key: (... if ... else ...) for new_key, old_val in zip(list1, list2)} Complex lists may require more intricate dictionary comprehension syntax. Techniques shown in this guide, such as using zip() and range() for iterations, help handle such cases. Converting a dictionary to a list is also possible in several ways, but it is much simpler. Tool Extracts Syntax list.keys() Keys list(old_dict.keys()) list.values() Values list(old_dict.values()) list.items() Key-Value Pairs list(old_dict.items()) Python offers flexible and efficient ways to convert structured data types between lists and dictionaries, enabling powerful manipulation and access.
13 January 2025 · 11 min to read

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