diff options
| -rw-r--r-- | julia.html.markdown | 154 |
1 files changed, 77 insertions, 77 deletions
diff --git a/julia.html.markdown b/julia.html.markdown index 15c09da4..839e414d 100644 --- a/julia.html.markdown +++ b/julia.html.markdown @@ -114,12 +114,12 @@ println("I'm Julia. Nice to meet you!") # => I'm Julia. Nice to meet you! #################################################### # You don't declare variables before assigning to them. -some_var = 5 # => 5 -some_var # => 5 +someVar = 5 # => 5 +someVar # => 5 # Accessing a previously unassigned variable is an error try - some_other_var # => ERROR: UndefVarError: some_other_var not defined + someOtherVar # => ERROR: UndefVarError: someOtherVar not defined catch e println(e) end @@ -286,62 +286,62 @@ d # => 5 e # => 4 # Dictionaries store mappings -empty_dict = Dict() # => Dict{Any,Any} with 0 entries +emptyDict = Dict() # => Dict{Any,Any} with 0 entries # You can create a dictionary using a literal -filled_dict = Dict("one" => 1, "two" => 2, "three" => 3) +filledDict = Dict("one" => 1, "two" => 2, "three" => 3) # => Dict{String,Int64} with 3 entries: # => "two" => 2, "one" => 1, "three" => 3 # Look up values with [] -filled_dict["one"] # => 1 +filledDict["one"] # => 1 # Get all keys -keys(filled_dict) +keys(filledDict) # => Base.KeySet for a Dict{String,Int64} with 3 entries. Keys: # => "two", "one", "three" # Note - dictionary keys are not sorted or in the order you inserted them. # Get all values -values(filled_dict) +values(filledDict) # => Base.ValueIterator for a Dict{String,Int64} with 3 entries. Values: # => 2, 1, 3 # Note - Same as above regarding key ordering. # Check for existence of keys in a dictionary with in, haskey -in(("one" => 1), filled_dict) # => true -in(("two" => 3), filled_dict) # => false -haskey(filled_dict, "one") # => true -haskey(filled_dict, 1) # => false +in(("one" => 1), filledDict) # => true +in(("two" => 3), filledDict) # => false +haskey(filledDict, "one") # => true +haskey(filledDict, 1) # => false # Trying to look up a non-existent key will raise an error try - filled_dict["four"] # => ERROR: KeyError: key "four" not found + filledDict["four"] # => ERROR: KeyError: key "four" not found catch e println(e) 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(dictionary, key, defaultValue) +get(filledDict, "one", 4) # => 1 +get(filledDict, "four", 4) # => 4 # Use Sets to represent collections of unordered, unique values -empty_set = Set() # => Set(Any[]) +emptySet = Set() # => Set(Any[]) # Initialize a set with values -filled_set = Set([1, 2, 2, 3, 4]) # => Set([4, 2, 3, 1]) +filledSet = Set([1, 2, 2, 3, 4]) # => Set([4, 2, 3, 1]) # Add more values to a set -push!(filled_set, 5) # => Set([4, 2, 3, 5, 1]) +push!(filledSet, 5) # => Set([4, 2, 3, 5, 1]) # Check if the values are in the set -in(2, filled_set) # => true -in(10, filled_set) # => false +in(2, filledSet) # => true +in(10, filledSet) # => false # There are functions for set intersection, union, and difference. -other_set = Set([3, 4, 5, 6]) # => Set([4, 3, 5, 6]) -intersect(filled_set, other_set) # => Set([4, 3, 5]) -union(filled_set, other_set) # => Set([4, 2, 3, 5, 6, 1]) +otherSet = Set([3, 4, 5, 6]) # => Set([4, 3, 5, 6]) +intersect(filledSet, otherSet) # => Set([4, 3, 5]) +union(filledSet, otherSet) # => Set([4, 2, 3, 5, 6, 1]) setdiff(Set([1,2,3,4]), Set([2,3,5])) # => Set([4, 1]) #################################################### @@ -349,15 +349,15 @@ setdiff(Set([1,2,3,4]), Set([2,3,5])) # => Set([4, 1]) #################################################### # Let's make a variable -some_var = 5 +someVar = 5 # Here is an if statement. Indentation is not meaningful in Julia. -if some_var > 10 - println("some_var is totally bigger than 10.") -elseif some_var < 10 # This elseif clause is optional. - println("some_var is smaller than 10.") +if someVar > 10 + println("someVar is totally bigger than 10.") +elseif someVar < 10 # This elseif clause is optional. + println("someVar is smaller than 10.") else # The else clause is optional too. - println("some_var is indeed 10.") + println("someVar is indeed 10.") end # => prints "some var is smaller than 10" @@ -434,8 +434,8 @@ add(5, 6) # => 11 # Compact assignment of functions -f_add(x, y) = x + y # => f_add (generic function with 1 method) -f_add(3, 4) # => 7 +fAdd(x, y) = x + y # => fAdd (generic function with 1 method) +fAdd(3, 4) # => 7 # Function can also return multiple values as tuple fn(x, y) = x + y, x - y # => fn (generic function with 1 method) @@ -478,67 +478,67 @@ catch e end # You can define functions that take keyword arguments -function keyword_args(;k1=4, name2="hello") # note the ; +function keywordArgs(;k1=4, name2="hello") # note the ; return Dict("k1" => k1, "name2" => name2) end -# => keyword_args (generic function with 1 method) +# => keywordArgs (generic function with 1 method) -keyword_args(name2="ness") # => ["name2"=>"ness", "k1"=>4] -keyword_args(k1="mine") # => ["name2"=>"hello", "k1"=>"mine"] -keyword_args() # => ["name2"=>"hello", "k1"=>4] +keywordArgs(name2="ness") # => ["name2"=>"ness", "k1"=>4] +keywordArgs(k1="mine") # => ["name2"=>"hello", "k1"=>"mine"] +keywordArgs() # => ["name2"=>"hello", "k1"=>4] # You can combine all kinds of arguments in the same function -function all_the_args(normal_arg, optional_positional_arg=2; keyword_arg="foo") - println("normal arg: $normal_arg") - println("optional arg: $optional_positional_arg") - println("keyword arg: $keyword_arg") +function allTheArgs(normalArg, optionalPositionalArg=2; keywordArg="foo") + println("normal arg: $normalArg") + println("optional arg: $optionalPositionalArg") + println("keyword arg: $keywordArg") end -# => all_the_args (generic function with 2 methods) +# => allTheArgs (generic function with 2 methods) -all_the_args(1, 3, keyword_arg=4) +allAheArgs(1, 3, keywordArg=4) # => normal arg: 1 # => optional arg: 3 # => keyword arg: 4 # Julia has first class functions -function create_adder(x) +function createAdder(x) adder = function (y) return x + y end return adder end -# => create_adder (generic function with 1 method) +# => createAdder (generic function with 1 method) # This is "stabby lambda syntax" for creating anonymous functions (x -> x > 2)(3) # => true -# This function is identical to create_adder implementation above. -function create_adder(x) +# This function is identical to createAdder implementation above. +function createAdder(x) y -> x + y end -# => create_adder (generic function with 1 method) +# => createAdder (generic function with 1 method) # You can also name the internal function, if you want -function create_adder(x) +function createAdder(x) function adder(y) x + y end adder end -# => create_adder (generic function with 1 method) +# => createAdder (generic function with 1 method) -add_10 = create_adder(10) # => (::getfield(Main, Symbol("#adder#11")){Int64}) +add10 = createAdder(10) # => (::getfield(Main, Symbol("#adder#11")){Int64}) # (generic function with 1 method) -add_10(3) # => 13 +add10(3) # => 13 # There are built-in higher order functions -map(add_10, [1,2,3]) # => [11, 12, 13] +map(add10, [1,2,3]) # => [11, 12, 13] filter(x -> x > 5, [3, 4, 5, 6, 7]) # => [6, 7] # We can use list comprehensions -[add_10(i) for i = [1, 2, 3]] # => [11, 12, 13] -[add_10(i) for i in [1, 2, 3]] # => [11, 12, 13] +[add10(i) for i = [1, 2, 3]] # => [11, 12, 13] +[add10(i) for i in [1, 2, 3]] # => [11, 12, 13] [x for x in [3, 4, 5, 6, 7] if x > 5] # => [6, 7] #################################################### @@ -616,7 +616,7 @@ supertype(SubString) # => AbstractString # <: is the subtyping operator struct Lion <: Cat # Lion is a subtype of Cat - mane_color + maneColor roar::AbstractString end @@ -627,7 +627,7 @@ Lion(roar::AbstractString) = Lion("green", roar) # This is an outer constructor because it's outside the type definition struct Panther <: Cat # Panther is also a subtype of Cat - eye_color + eyeColor Panther() = new("green") # Panthers will only have this constructor, and no default constructor. end @@ -669,14 +669,14 @@ Lion <: Cat # => true Panther <: Cat # => true # Defining a function that takes Cats -function pet_cat(cat::Cat) +function petCat(cat::Cat) println("The cat says $(meow(cat))") end -# => pet_cat (generic function with 1 method) +# => petCat (generic function with 1 method) -pet_cat(Lion("42")) # => The cat says 42 +petCat(Lion("42")) # => The cat says 42 try - pet_cat(tigger) # => ERROR: MethodError: no method matching pet_cat(::Tiger) + petCat(tigger) # => ERROR: MethodError: no method matching petCat(::Tiger) catch e println(e) end @@ -695,7 +695,7 @@ fight(tigger, Panther()) # => The orange tiger wins! fight(tigger, Lion("ROAR")) # => 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.maneColor)-maned lion wins!") # => fight (generic function with 2 methods) fight(tigger, Panther()) # => The orange tiger wins! @@ -744,14 +744,14 @@ fight(Lion("RAR"), Lion("brown", "rarrr")) # => The lions come to a tie # Under the hood # You can take a look at the llvm and the assembly code generated. -square_area(l) = l * l # square_area (generic function with 1 method) +squareArea(l) = l * l # squareArea (generic function with 1 method) -square_area(5) # => 25 +squareArea(5) # => 25 -# What happens when we feed square_area an integer? -code_native(square_area, (Int32,), syntax = :intel) +# What happens when we feed squareArea an integer? +codeNative(squareArea, (Int32,), syntax = :intel) # .text - # ; Function square_area { + # ; Function squareArea { # ; Location: REPL[116]:1 # Prologue # push rbp # mov rbp, rsp @@ -765,9 +765,9 @@ code_native(square_area, (Int32,), syntax = :intel) # nop dword ptr [rax + rax] # ;} -code_native(square_area, (Float32,), syntax = :intel) +codeNative(squareArea, (Float32,), syntax = :intel) # .text - # ; Function square_area { + # ; Function squareArea { # ; Location: REPL[116]:1 # push rbp # mov rbp, rsp @@ -780,9 +780,9 @@ code_native(square_area, (Float32,), syntax = :intel) # nop word ptr [rax + rax] # ;} -code_native(square_area, (Float64,), syntax = :intel) +codeNative(squareArea, (Float64,), syntax = :intel) # .text - # ; Function square_area { + # ; Function squareArea { # ; Location: REPL[116]:1 # push rbp # mov rbp, rsp @@ -798,12 +798,12 @@ code_native(square_area, (Float64,), syntax = :intel) # Note that julia will use floating point instructions if any of the # arguments are floats. # Let's calculate the area of a circle -circle_area(r) = pi * r * r # circle_area (generic function with 1 method) -circle_area(5) # 78.53981633974483 +circleArea(r) = pi * r * r # circleArea (generic function with 1 method) +circleArea(5) # 78.53981633974483 -code_native(circle_area, (Int32,), syntax = :intel) +codeNative(circleArea, (Int32,), syntax = :intel) # .text - # ; Function circle_area { + # ; Function circleArea { # ; Location: REPL[121]:1 # push rbp # mov rbp, rsp @@ -832,9 +832,9 @@ code_native(circle_area, (Int32,), syntax = :intel) # nop dword ptr [rax] # ;} -code_native(circle_area, (Float64,), syntax = :intel) +codeNative(circleArea, (Float64,), syntax = :intel) # .text - # ; Function circle_area { + # ; Function circleArea { # ; Location: REPL[121]:1 # push rbp # mov rbp, rsp |