Functions

Functions are the basic building blocks of a programme. They allow you to organise your code, make it more readable and reusable. In Julia, functions can be simple or complex, depending on the task at hand. If you’re just starting out on your programming journey, functions are something you’ll be working with all the time. They help you break down complex tasks into smaller, more manageable pieces.

Defining a function

Functions in Julia are defined using the function keyword. They can return values using return or automatically return the result of the last expression. Let’s look at an example:

function fname(x, y)
  z = x^2
  z + 4y
end

In this example, the function fname takes two arguments x and y, calculates the square of x and adds 4y to it. The result of the last expression (z + 4y) is automatically returned as the result of the function.

For a more compact function definition, you can use the abbreviated syntax:

gname(x, y) = x^2 + 4y

This syntax is convenient for simple functions that can be written in a single line. It makes the code more concise and easy to read.

Function call

Functions are called by name with arguments passed in parentheses. This allows you to perform calculations and get results. For example:

z = fname(3, 1)

Output

Here, the function fname is called with arguments 3 and 1 and the result is stored in the variable z.

Example with comments

# Функция для вычисления площади прямоугольника
function calculate_area(width, height)
  area = width * height  # Вычисляем площадь
  return area  # Возвращаем результат
end

# Вызов функции и вывод результата
result = calculate_area(5, 10)
println("Площадь прямоугольника: ", result)