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--- programming:python:dictionary [2022/06/02 16:48] – levor
+++ programming:python:dictionary [2022/06/06 18:29] (current) – levor
@@ Line 2: / Line 2: @@
 ^example^explanation / remarks^
-|d = {}| empty dictionary |
+|d = {}|construct an empty dictionary |
-|d = {"age": 17, "school": "Adam High School", "transportation": "bus"}| construct with data |
+|d = {"age": 17, "school": "Adam High School", "transportation": "bus"}|construct a dictionary with data|
-|dict["age"]=18| add or change value of a key|
+|d["age"]=18| add or change value of a key|
-|v = dict["age"]| get value associated with a key |
+|v = d["age"]| get value associated with a key |
-|del dict["school"]| delete a //key,value// pair based on key|
+|l = len(d)| get number of keys (which is the same as number of values)|
-|l = len(d)| get number of keys (same as number of values...)|
 |for key,val in d.items(): \\ ...| loop over all //key,val// pairs |
+|d.clear()|delete all entries|
+|d.copy()|returns a (shallow!) copy of the dictionary|
+|d.get(key, default=None)|returns a value associated with a //key//. if //key// not found -> return //default//|
+|d.setdefault(key, default=None)|if //key// exist -> do nothing. if not -> add the specified //key,default// pair|
+|d.fromkeys(seq, value=None)|//seq//=list of keys. add these keys to the dictionary, all having same associated value=//value// |
+|d.has_key(key)|returns a boolean value: True if key exists, else -> False|
+|d.keys()|returns a list of the keys: [key1, key2, ...]|
+|d.values()|returns an **iterable** of the values|
+|d**.items()**|returns a list of tuples: [(key1,val1),(key2,val2),...]|
+|d.update(d2)|add all d2 //key,value// pairs to d|
+|del dict["school"]| delete a //key,value// pair based on key|
 |type(d)| <class 'dict'> |
 |cmp(d1, d2)| compares two dictionaries [need more info!]|
-|d.clear()|delete all entries|