diff options
author | Martijn Visser <mgvisser@gmail.com> | 2018-08-14 18:00:00 +0200 |
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committer | Martijn Visser <mgvisser@gmail.com> | 2018-08-14 18:00:00 +0200 |
commit | cf5cc6b76cb3978818dc98feef86f62b1b406e63 (patch) | |
tree | b87855c8fd840332f85ec9fd008e91131b1c40dc /julia.html.markdown | |
parent | e9dd72024cee9805f9d763387d4c848a316a7307 (diff) |
autoformat with VS code
mostly just spaces between arguments
Diffstat (limited to 'julia.html.markdown')
-rw-r--r-- | julia.html.markdown | 140 |
1 files changed, 70 insertions, 70 deletions
diff --git a/julia.html.markdown b/julia.html.markdown index d55a166b..2e4e7c48 100644 --- a/julia.html.markdown +++ b/julia.html.markdown @@ -31,7 +31,7 @@ This is based on Julia 1.0.0 3 # => 3 (Int64) 3.2 # => 3.2 (Float64) 2 + 1im # => 2 + 1im (Complex{Int64}) -2//3 # => 2//3 (Rational{Int64}) +2 // 3 # => 2//3 (Rational{Int64}) # All of the normal infix operators are available. 1 + 1 # => 2 @@ -41,7 +41,7 @@ This is based on Julia 1.0.0 5 / 2 # => 2.5 # dividing an Int by an Int always results in a Float div(5, 2) # => 2 # for a truncated result, use div 5 \ 35 # => 7.0 -2 ^ 2 # => 4 # power, not bitwise xor +2^2 # => 4 # power, not bitwise xor 12 % 10 # => 2 # Enforce precedence with parentheses @@ -83,7 +83,7 @@ false # Strings are created with " try -"This is a string." + "This is a string." catch ; end # Julia has several types of strings, including ASCIIString and UTF8String. @@ -91,19 +91,19 @@ catch ; end # Character literals are written with ' try -'a' + 'a' catch ; end # Some strings can be indexed like an array of characters try -"This is a string"[1] # => 'T' # Julia indexes from 1 + "This is a string"[1] # => 'T' # Julia indexes from 1 catch ; end # However, this is will not work well for UTF8 strings, # so iterating over strings is recommended (map, for loops, etc). # $ can be used for string interpolation: try -"2 + 2 = $(2 + 2)" # => "2 + 2 = 4" + "2 + 2 = $(2 + 2)" # => "2 + 2 = 4" catch ; end # You can put any Julia expression inside the parentheses. @@ -116,7 +116,7 @@ println("I'm Julia. Nice to meet you!") # String can be compared lexicographically "good" > "bye" # => true "good" == "good" # => true -"1 + 2 = 3" == "1 + 2 = $(1+2)" # => true +"1 + 2 = 3" == "1 + 2 = $(1 + 2)" # => true #################################################### ## 2. Variables and Collections @@ -172,17 +172,17 @@ matrix = [1 2; 3 4] # => 2x2 Int64 Array: [1 2; 3 4] b = Int8[4, 5, 6] # => 3-element Int8 Array: [4, 5, 6] # Add stuff to the end of a list with push! and append! -push!(a,1) # => [1] -push!(a,2) # => [1,2] -push!(a,4) # => [1,2,4] -push!(a,3) # => [1,2,4,3] -append!(a,b) # => [1,2,4,3,4,5,6] +push!(a, 1) # => [1] +push!(a, 2) # => [1,2] +push!(a, 4) # => [1,2,4] +push!(a, 3) # => [1,2,4,3] +append!(a, b) # => [1,2,4,3,4,5,6] # Remove from the end with pop pop!(b) # => 6 and b is now [4,5] # Let's put it back -push!(b,6) # b is now [4,5,6] again. +push!(b, 6) # b is now [4,5,6] again. a[1] # => 1 # remember that Julia indexes from 1, not 0! @@ -192,7 +192,7 @@ a[end] # => 6 # we also have shift and unshift shift!(a) # => 1 and a is now [2,4,3,4,5,6] -unshift!(a,7) # => [7,2,4,3,4,5,6] +unshift!(a, 7) # => [7,2,4,3,4,5,6] # Function names that end in exclamations points indicate that they modify # their argument. @@ -203,7 +203,7 @@ sort!(arr) # => [4,5,6]; arr is now [4,5,6] # Looking out of bounds is a BoundsError try a[0] # => ERROR: BoundsError() in getindex at array.jl:270 - a[end+1] # => ERROR: BoundsError() in getindex at array.jl:270 + a[end + 1] # => ERROR: BoundsError() in getindex at array.jl:270 catch e println(e) end @@ -221,11 +221,11 @@ a[2:end] # => [2, 3, 4, 5] # Remove elements from an array by index with splice! arr = [3,4,5] -splice!(arr,2) # => 4 ; arr is now [3,5] +splice!(arr, 2) # => 4 ; arr is now [3,5] # Concatenate lists with append! b = [1,2,3] -append!(a,b) # Now a is [1, 2, 3, 4, 5, 1, 2, 3] +append!(a, b) # Now a is [1, 2, 3, 4, 5, 1, 2, 3] # Check for existence in a list with in in(1, a) # => true @@ -236,7 +236,7 @@ length(a) # => 8 # Tuples are immutable. tup = (1, 2, 3) # => (1,2,3) # an (Int64,Int64,Int64) tuple. tup[1] # => 1 -try: + try: tup[1] = 3 # => ERROR: no method setindex!((Int64,Int64,Int64),Int64,Int64) catch e println(e) @@ -265,7 +265,7 @@ e, d = d, e # => (5,4) # d is now 5 and e is now 4 empty_dict = Dict() # => Dict{Any,Any}() # You can create a dictionary using a literal -filled_dict = Dict("one"=> 1, "two"=> 2, "three"=> 3) +filled_dict = Dict("one" => 1, "two" => 2, "three" => 3) # => Dict{ASCIIString,Int64} # Look up values with [] @@ -296,8 +296,8 @@ end # Use the get method to avoid that error by providing a default value # get(dictionary,key,default_value) -get(filled_dict,"one",4) # => 1 -get(filled_dict,"four",4) # => 4 +get(filled_dict, "one", 4) # => 1 +get(filled_dict, "four", 4) # => 4 # Use Sets to represent collections of unordered, unique values empty_set = Set() # => Set{Any}() @@ -305,7 +305,7 @@ empty_set = Set() # => Set{Any}() filled_set = Set([1,2,2,3,4]) # => Set{Int64}(1,2,3,4) # Add more values to a set -push!(filled_set,5) # => Set{Int64}(5,4,2,3,1) +push!(filled_set, 5) # => Set{Int64}(5,4,2,3,1) # Check if the values are in the set in(2, filled_set) # => true @@ -315,7 +315,7 @@ in(10, filled_set) # => false other_set = Set([3, 4, 5, 6]) # => Set{Int64}(6,4,5,3) intersect(filled_set, other_set) # => Set{Int64}(3,4,5) union(filled_set, other_set) # => Set{Int64}(1,2,3,4,5,6) -setdiff(Set([1,2,3,4]),Set([2,3,5])) # => Set{Int64}(1,4) +setdiff(Set([1,2,3,4]), Set([2,3,5])) # => Set{Int64}(1,4) #################################################### @@ -338,7 +338,7 @@ end # For loops iterate over iterables. # Iterable types include Range, Array, Set, Dict, and AbstractString. -for animal=["dog", "cat", "mouse"] +for animal = ["dog", "cat", "mouse"] println("$animal is a mammal") # You can use $ to interpolate variables or expression into strings end @@ -356,7 +356,7 @@ end # cat is a mammal # mouse is a mammal -for a in Dict("dog"=>"mammal","cat"=>"mammal","mouse"=>"mammal") +for a in Dict("dog" => "mammal", "cat" => "mammal", "mouse" => "mammal") println("$(a[1]) is a $(a[2])") end # prints: @@ -364,7 +364,7 @@ end # cat is a mammal # mouse is a mammal -for (k,v) in Dict("dog"=>"mammal","cat"=>"mammal","mouse"=>"mammal") +for (k, v) in Dict("dog" => "mammal", "cat" => "mammal", "mouse" => "mammal") println("$k is a $v") end # prints: @@ -386,9 +386,9 @@ end # Handle exceptions with a try/catch block try - error("help") + error("help") catch e - println("caught it $e") + println("caught it $e") end # => caught it ErrorException("help") @@ -426,7 +426,7 @@ function varargs(args...) end # => varargs (generic function with 1 method) -varargs(1,2,3) # => (1,2,3) +varargs(1, 2, 3) # => (1,2,3) # The ... is called a splat. # We just used it in a function definition. @@ -434,18 +434,18 @@ varargs(1,2,3) # => (1,2,3) # where it will splat an Array or Tuple's contents into the argument list. add([5,6]...) # this is equivalent to add(5,6) -x = (5,6) # => (5,6) +x = (5, 6) # => (5,6) add(x...) # this is equivalent to add(5,6) # You can define functions with optional positional arguments -function defaults(a,b,x=5,y=6) +function defaults(a, b, x=5, y=6) return "$a $b and $x $y" end -defaults('h','g') # => "h g and 5 6" -defaults('h','g','j') # => "h g and j 6" -defaults('h','g','j','k') # => "h g and j k" +defaults('h', 'g') # => "h g and 5 6" +defaults('h', 'g', 'j') # => "h g and j 6" +defaults('h', 'g', 'j', 'k') # => "h g and j k" try defaults('h') # => ERROR: no method defaults(Char,) defaults() # => ERROR: no methods defaults() @@ -454,8 +454,8 @@ catch e end # You can define functions that take keyword arguments -function keyword_args(;k1=4,name2="hello") # note the ; - return Dict("k1"=>k1,"name2"=>name2) +function keyword_args(;k1=4, name2="hello") # note the ; + return Dict("k1" => k1, "name2" => name2) end keyword_args(name2="ness") # => ["name2"=>"ness","k1"=>4] @@ -508,7 +508,7 @@ map(add_10, [1,2,3]) # => [11, 12, 13] filter(x -> x > 5, [3, 4, 5, 6, 7]) # => [6, 7] # We can use list comprehensions for nicer maps -[add_10(i) for i=[1, 2, 3]] # => [11, 12, 13] +[add_10(i) for i = [1, 2, 3]] # => [11, 12, 13] [add_10(i) for i in [1, 2, 3]] # => [11, 12, 13] #################################################### @@ -537,16 +537,16 @@ typeof(DataType) # => DataType # ... # end type Tiger - taillength::Float64 - coatcolor # not including a type annotation is the same as `::Any` + taillength::Float64 + coatcolor # not including a type annotation is the same as `::Any` end # The default constructor's arguments are the properties # of the type, in the order they are listed in the definition -tigger = Tiger(3.5,"orange") # => Tiger(3.5,"orange") +tigger = Tiger(3.5, "orange") # => Tiger(3.5,"orange") # The type doubles as the constructor function for values of that type -sherekhan = typeof(tigger)(5.6,"fire") # => Tiger(5.6,"fire") +sherekhan = typeof(tigger)(5.6, "fire") # => Tiger(5.6,"fire") # These struct-style types are called concrete types # They can be instantiated, but cannot have subtypes. @@ -588,19 +588,19 @@ supertype(DirectIndexString) # => AbstractString # <: is the subtyping operator type Lion <: Cat # Lion is a subtype of Cat - mane_color - roar::AbstractString + mane_color + roar::AbstractString end # You can define more constructors for your type # Just define a function of the same name as the type # and call an existing constructor to get a value of the correct type -Lion(roar::AbstractString) = Lion("green",roar) +Lion(roar::AbstractString) = Lion("green", roar) # This is an outer constructor because it's outside the type definition type Panther <: Cat # Panther is also a subtype of Cat - eye_color - Panther() = new("green") + eye_color + Panther() = new("green") # Panthers will only have this constructor, and no default constructor. end # Using inner constructors, like Panther does, gives you control @@ -619,30 +619,30 @@ end # Definitions for Lion, Panther, Tiger function meow(animal::Lion) - animal.roar # access type properties using dot notation + animal.roar # access type properties using dot notation end function meow(animal::Panther) - "grrr" + "grrr" end function meow(animal::Tiger) - "rawwwr" + "rawwwr" end # Testing the meow function meow(tigger) # => "rawwr" -meow(Lion("brown","ROAAR")) # => "ROAAR" +meow(Lion("brown", "ROAAR")) # => "ROAAR" meow(Panther()) # => "grrr" # Review the local type hierarchy -issubtype(Tiger,Cat) # => false -issubtype(Lion,Cat) # => true -issubtype(Panther,Cat) # => true +issubtype(Tiger, Cat) # => false +issubtype(Lion, Cat) # => true +issubtype(Panther, Cat) # => true # Defining a function that takes Cats function pet_cat(cat::Cat) - println("The cat says $(meow(cat))") + println("The cat says $(meow(cat))") end pet_cat(Lion("42")) # => prints "The cat says 42" @@ -657,47 +657,47 @@ end # In Julia, all of the argument types contribute to selecting the best method. # Let's define a function with more arguments, so we can see the difference -function fight(t::Tiger,c::Cat) - println("The $(t.coatcolor) tiger wins!") +function fight(t::Tiger, c::Cat) + println("The $(t.coatcolor) tiger wins!") end # => fight (generic function with 1 method) -fight(tigger,Panther()) # => prints The orange tiger wins! -fight(tigger,Lion("ROAR")) # => prints The orange tiger wins! +fight(tigger, Panther()) # => prints The orange tiger wins! +fight(tigger, Lion("ROAR")) # => prints The orange tiger wins! # Let's change the behavior when the Cat is specifically a Lion -fight(t::Tiger,l::Lion) = println("The $(l.mane_color)-maned lion wins!") +fight(t::Tiger, l::Lion) = println("The $(l.mane_color)-maned lion wins!") # => fight (generic function with 2 methods) -fight(tigger,Panther()) # => prints The orange tiger wins! -fight(tigger,Lion("ROAR")) # => prints The green-maned lion wins! +fight(tigger, Panther()) # => prints The orange tiger wins! +fight(tigger, Lion("ROAR")) # => prints The green-maned lion wins! # We don't need a Tiger in order to fight -fight(l::Lion,c::Cat) = println("The victorious cat says $(meow(c))") +fight(l::Lion, c::Cat) = println("The victorious cat says $(meow(c))") # => fight (generic function with 3 methods) -fight(Lion("balooga!"),Panther()) # => prints The victorious cat says grrr +fight(Lion("balooga!"), Panther()) # => prints The victorious cat says grrr try - fight(Panther(),Lion("RAWR")) + fight(Panther(), Lion("RAWR")) catch e - println(e) + println(e) # => MethodError(fight, (Panther("green"), Lion("green", "RAWR")), 0x000000000000557b) end # Also let the cat go first -fight(c::Cat,l::Lion) = println("The cat beats the Lion") +fight(c::Cat, l::Lion) = println("The cat beats the Lion") # This warning is because it's unclear which fight will be called in: try - fight(Lion("RAR"),Lion("brown","rarrr")) # => prints The victorious cat says rarrr + fight(Lion("RAR"), Lion("brown", "rarrr")) # => prints The victorious cat says rarrr catch e - println(e) + println(e) # => MethodError(fight, (Lion("green", "RAR"), Lion("brown", "rarrr")), 0x000000000000557c) end # The result may be different in other versions of Julia -fight(l::Lion,l2::Lion) = println("The lions come to a tie") -fight(Lion("RAR"),Lion("brown","rarrr")) # => prints The lions come to a tie +fight(l::Lion, l2::Lion) = println("The lions come to a tie") +fight(Lion("RAR"), Lion("brown", "rarrr")) # => prints The lions come to a tie # Under the hood |