Notes

• java

• python

  • OrderedDict

Operations

{% highlight python %}

python

create

demodict = {} # empty dict demodict = {'a':'1', 'b':'2'} demodict = dict(a=1, b=2) demood = OrderedDict()

retrieve

demodict.get(key) # absent returns None demodict.get(key, default) demodict.keys(), demodict.values(), demodict.items() demodict.iterkeys(), demodict.itervalues(), demodict.iteritems()

update

demodict[key] = new_value demodict.update(otherdict) # merge demodict.setdefault(key, value) # return existing value of key or new value of new key

delete

demodict.pop(key), demodict.popitem() del demodict[key]

others

"b" in demodict True

demodict.viewitems() # return type dict_items for set operation &(intersaction), | (union), -(difference), ^ (symmetric difference)

Convert

list = [(1,2), (3,4)] list [(1, 2), (3, 4)] dict((x,y) for x,y in list) {1: 2, 3: 4} {% endhighlight %}

{% highlight go %} /*** go ***/ // create var demoMap map[string] demoStruct demoMap = make(map[string], demoStruct, ) # initCap is optional

// retrieve value, ok := demoMap[key]

// update demoMap[key] = value

// delete delete(demoMap, key)

{% endhighlight %}