Variables in Julia

Just as in other programming languages, we use a variable to store a value that is obtained from a computation or external source.

Start the REPL by typing julia in the Terminal:

$ julia

# assign 100 to a variable x
julia> x = 100
100

# multiple the value in the variable by 5
julia> x*5
500

We can change the values stored in a variable or mutate the state:

# assign a different value to x
# this will replace the existing value in x
julia> x = 24
24

# create another variable y
julia> y = 10
10

Simple operations, such as swapping, are easy:

# swap values of x and y
julia> x,y = y,x
(10,24)

julia> x
10
julia> y
24

The names of variables can start with a character or a "_" (underscore). Julia also allows Unicode names (UTF-8), but not all Unicode names are accepted in the variable name:

julia> _ab = 40
40
julia> @ab = 10
ERROR: syntax: unexpected "="
julia> 1000
1000

Please note "!" (exclamation mark) shouldn't be used in the variable name as functions...