diff options
| -rw-r--r-- | julia.html.markdown | 42 |
1 files changed, 18 insertions, 24 deletions
diff --git a/julia.html.markdown b/julia.html.markdown index b036b1dd..e60b4e52 100644 --- a/julia.html.markdown +++ b/julia.html.markdown @@ -180,43 +180,37 @@ e, d = d, e #=> (5,4) # d is now 5 and e is now 4 # Dictionaries store mappings -empty_dict = {} +empty_dict = Dict() #=> Dict{Any,Any}() # Here is a prefilled dictionary -filled_dict = {"one": 1, "two": 2, "three": 3} +filled_dict = ["one"=> 1, "two"=> 2, "three"=> 3] #=> ["one"=> 1, "two"=> 2, "three"=> 3] # Dict{ASCIIString,Int64} # Look up values with [] filled_dict["one"] #=> 1 -# Get all keys as a list -filled_dict.keys() #=> ["three", "two", "one"] +# Get all keys +keys(filled_dict) #=> KeyIterator{Dict{ASCIIString,Int64}}(["three"=>3,"one"=>1,"two"=>2]) # Note - Dictionary key ordering is not guaranteed. # Your results might not match this exactly. -# Get all values as a list -filled_dict.values() #=> [3, 2, 1] +# Get all values +values(d) #=> ValueIterator{Dict{ASCIIString,Int64}}(["three"=>3,"one"=>1,"two"=>2]) # Note - Same as above regarding key ordering. -# Check for existence of keys in a dictionary with in -"one" in filled_dict #=> True -1 in filled_dict #=> False +# Check for existence of keys in a dictionary with contains, haskey +contains(filled_dict,("one",1)) #=> true +contains(filled_dict,("two",3)) #=> false +haskey(filled_dict,"one") #=> true +haskey(filled_dict,1) #=> false -# Trying to look up a non-existing key will raise a KeyError -filled_dict["four"] #=> KeyError +# Trying to look up a non-existing key will raise an error +filled_dict["four"] #=> ERROR: key not found: four in getindex at dict.jl:489 -# Use get method to avoid the KeyError -filled_dict.get("one") #=> 1 -filled_dict.get("four") #=> None +# Use get method to avoid the error +# get(dictionary,key,default_value) +get(filled_dict,"one",4) #=> 1 +get(filled_dict,"four",4) #=> 4 -# The get method supports a default argument when the value is missing -filled_dict.get("one", 4) #=> 1 -filled_dict.get("four", 4) #=> 4 - -# Setdefault method is a safe way to add new key-value pair into dictionary -filled_dict.setdefault("five", 5) #filled_dict["five"] is set to 5 -filled_dict.setdefault("five", 6) #filled_dict["five"] is still 5 - - -# Sets store ... well sets +# Sets store sets empty_set = set() # Initialize a set with a bunch of values some_set = set([1,2,2,3,4]) # filled_set is now set([1, 2, 3, 4]) |