Julia

Basics

  • To import packages, use using or import.
  • Install package via Julia’s package manager, in the Julia’s console by typing ] and then add Flux
  • Equivalently, via the Pkg API:
import Pkg
Pkg.add("Flux")
  • Uninstall package via Julia’s package manager, in the Julia’s console by typing ] and then remove Flux or rm Flux
  • To go back to Julia’s interpreter, click backspace key.
answer = 42 # Variable assignments
x, y, z = 1, [1:10;], "Hello World" # Multiple assignment
z, y = y, z  # swap x and y

const pi = 3.14 # Constant declaration

i = 1 # End-of-line
#=
Delimited Comment
OR Multi-line comment
=#

0 < i < 3  # Chaining
5 < x != i < 5

# function definitions
function add_one(i)
  return i+1
end

Operators

+, -, *, /, % # Basic arithmetic
2^3  # Exponentiation
3/12  # Fractional division
7\3  # Inverse division. It's same as 1/(7/3)
!true  # Logical negation
1 == 2 # Equality
1 != 2 # Inequality
1  2 # Inequality where you can use unicode symbols
1 < 2 # Less than
2 > 3 # Greater than
1 <= 2 # Less than or equal to
1  2 # use of unicode
1 >= 2 # Greater than or equal to. OR ≥

[1, 2, 3] .+ [1, 3, 3] == [1+1, 2+3, 3+3] == [2, 5, 6]  # Element-wise addition operation
[1, 2, 3] .* [1, 2, 3] == [1, 4, 9]  # Element-wise multiplication operation

isnan(NaN)  # Check for if NaN is a REALLY Not a Number (NaN)
isnan(1/0)  # Check for if Infinity is a NaN

a, b = 1, 0
a == b ? "Equal" : "Not equal"  # Ternary operator
a && b  # Logical AND operator
a || b  # Logical OR operator
a === b  # Object equivalence OR strict equality

Permalink at https://www.physicslog.com/cs-notes/julia

Published on May 28, 2021

Last revised on Apr 3, 2022

References