println("Hello, World")
#> Hello, World
1 Introduction
1.1 Hello World
println()
print to newline.
1.2 Assign Variable
Dynamic typing
= 10
my_int #> 10
typeof(my_int)
#> Int64
= 3.1416
my_pi #> 3.1416
typeof(my_pi)
#> Float64
= "smily cat"
😸 #> "smily cat"
typeof(😸)
#> String
Sting interpolation with $
"This is $😸"
#> "This is smily cat"
= 1
😀 = -1
😞 = 0 🤐
== 😀 + 😞
🤐 #> true
1.3 Comment
# This is comment
#=
This
is
Multiline Comment
=#
1.4 Basic Math
1 + 1
#> 2
1 - 1
#> 0
2 * 3
#> 6
3 / 2
#> 1.5
like R
10 ^ 2
#> 100
like Python
5 % 2
#> 1
1.5 Operator
Boolean Operators
true
!#> false
false && true
#> false
false || true
#> true
Logical Operator ignore type
1 == 1.0
#> true
1.6 Vectorized “dot” operators
1,2,3] ^ 3
[# This would Error
1,2,3] .^ 3
[#> 3-element Vector{Int64}:
#> 1
#> 8
#> 27
a .^ b
is parsed as the “dot” call (^).(a,b)
, which performs a broadcast operation:
- combine arrays and scalars,
- arrays of the same size (performing the operation elementwise)
- even arrays of different shapes (e.g. combining row and column vectors to produce a matrix).
1.7 Exercise
convert()
function
= 365 days
= convert(Float64, days) # Convert to Float64
days_float #> 365.0
== days_float
days #> true
@assert days == 365
@assert days_float == 365.0
convert(Int64, "1") # Error
parse(Int64, "1")
#> 1