Published May 29, 2024
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In Julia, variables are used to store data. They can hold various data types and are mutable by default, allowing their values to be changed after assignment.


variable_name = value
  • variable_name: This is the chosen name for the variable, following Julia’s naming rules and conventions.
  • value: Represents the data or value assigned to the variable, which can be of various types supported by Julia.


integer_variable = 10
float_variable = 3.14
string_variable = "Julia"
boolean_variable = true
println("Integer variable: ", integer_variable)
println("Float variable: ", float_variable)
println("String variable: ", string_variable)
println("Boolean variable: ", boolean_variable)

The output for the above code is as follows:

Integer variable: 10
Float variable: 3.14
String variable: Julia
Boolean variable: true

Variable Nomenclature

When declaring a variable in Julia, the variable name goes first, optionally followed by a type annotation and then the value.

If a variable does not need a value to be assigned immediately, it can be declared without a type and a value can be assigned later:

name = value # Without type annotation
name::Type = value # With type annotation

Note: Variables in Julia are dynamic and can hold values of different types, but you can optionally declare the type for performance optimization and type-checking.

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