Common values

In this section, we provide a quick introduction to common basic objects. The function typeof used below returns the type of object provided as argument.

• Logical

true

true

false

false

typeof(true)

Bool

• Integers

1

1

typeof(1)

Int64

Int8(1)

1

typeof(Int8(1))

Int8

• Floating-Point numbers

10.0

10.0

typeof(10.0)

Float64

Float16(10.0)

Float16(10.0)

typeof(Float16(1))

Float16

• Complex numbers

1 + 2im

1 + 2im

typeof(1 + 2im)

Complex{Int64}

• Rational numbers

10 // 15

2//3

typeof(10 // 15)

Rational{Int64}

• Character

'x'

'x': ASCII/Unicode U+0078 (category Ll: Letter, lowercase)

typeof('x')

Char

typeof('β')

Char

• Strings

"julia"

"julia"

typeof("julia")

String

• Symbol: Object used to represent identifiers

:name

:name

typeof(:name)

Symbol

• Tuples: Unmutable fixed-length container holding any values

("John", 29, 10.0)

("John", 29, 10.0)

typeof(("John", 29, 10.0))

Tuple{String, Int64, Float64}

• Named tuples: Tuples with element names

(name = "John", age = 29, value = 10.0)

(name = "John", age = 29, value = 10.0)

typeof((name = "John", age = 29, value = 10.0))

NamedTuple{(:name, :age, :value), Tuple{String, Int64, Float64}}

• Pair: Unmutable object with two elements (first and second)

"January" => 1

"January" => 1

typeof("January" => 1)

Pair{String, Int64}

• Dictionaries: Table with keys and values.

Dict("Poisson" => 1, "Gaussian" => 2)

Dict{String, Int64} with 2 entries:
  "Gaussian" => 2
  "Poisson"  => 1

typeof(Dict("Poisson" => 1, "Gaussian" => 2))

Dict{String, Int64}