Python Day5 Dictionary

Python dictionary

# Data Type partitioning: mutable data type, immutable data type # immutable data type: ganso bool str int HASH # mutable data type: List Dict (dictionary) set (set) non-hash # Dict key (must be hash) value (Arbitrary data class # dict Advantages: Fast query speed (binary search) # Store A lot of relational data # Features: unordered (before 3.5 version) Dic1 = {"Age": "" Name ":" Break "," sex ":" male "}# increase D ic1["hobby"] = "girly" # does not add # print (DIC1) # {' Age ': ' ' name ': ' Break ', ' hobby ': ' Giry ', ' sex ': ' Male '}dic1.setdef Ault ("Game") # does not increase, there is an overlay (the default value added is None) # print (dic1) # {' Sex ': ' Male ', ' age ': ', ' ' name ': ' Break ', ' game ': none, ' Hobb Y ': ' girly '}# delete dic1.pop ("game") # Pass in the key to be deleted (The return value is the value of the corresponding key) # Print (Dic1.pop ("Break666", "no corresponding key (None)") # If you need to delete the K EY will return a second parameter < no corresponding key (none) ># print (dic1) # {' Hobby ': ' girly ', ' age ': ' Sex ': ' Male ', ' name ': ' Break '}# p  Rint (Dic1.popitem ()) # randomly delete the 3.6 version after the default delete the last one returns a tuple (' name ', ' Break ') # print (dic1) # {' Hobby ': ' girly ', ' sex ': ' Male ', ' Age ': 18}del dic1["Hobby"] # Delete the corresponding key if key does not have an error, it is recommended to use pop# print (DIC1) # {' Sex ': ' Male ', ' name ': ' Break ', ' age ': 18}# Del dic1 # Direct Delete Dictionary # PRint (DIC1) # error nameerror:name ' Dic1 ' is not defined# dic1.clear () # Empty Dictionary # Print (dic1) # {}# change dic1[' age '] = 19 # Direct Assignment Print (DIC1) # updatediv = {"Name": "Box", "width": "200px", "height": "200px", "Background-color": "Red"}dic1.update (div) # Update Div to dic1 inside only change dic1,div do not change # print (dic1) # {' Sex ': ' Male ', ' height ': ' 200px ', ' width ': ' 200 Px ', ' age ': +, ' name ': ' Box ', ' background-color ': ' Red '}# print (div) # {' Name ': ' box ', ' Height ': ' 200px ', ' width ': ' 200p X ', ' background-color ': ' Red '}# as List with # print (Dic1.keys (), type (# Dic1.keys ())) # Type is the dictionary key type (dict_keys) Dict_keys (['     Background-color ', ' age ', ' width ', ' name ', ' sex ', ' height ']) # <class ' Dict_keys ' ># print (Dic1.values (), type (# Dic1.values ()) # type is the dictionary values type (dict_values) dict_values ([' Red ', ' 200px ', ' box ', ' Male ', ' 200px ')] <class# ' Dict_values ' ># print (Dic1.items (), type (# Dic1.items ())) # type is the dictionary items type (dict_items) dict_items ([' Background-color ', ' Red '), (' age ', +), (' WidtH ', ' 200px '), (' Name ', # ' box '), (' Sex ', ' Male '), (' Height ', ' 200px ')]) <class ' Dict_items ' >a, b, C = [1, 2, 3]print ( A, B, c) ' For I in Dic1:print (i) # All is key print (Dic1[i]) # All is value ' # for K, V in Dic1.items (): # Prin T (k, v) # Get Get key value # print (dic1["name1"]) # error # Print (Dic1.get ("name1", "no This Key")) # no default return of none can change the default return value ' info = Input (">>>") for I in Info:if I.isalpha (): info = info.replace (i, "") Print (Len (info.sp Lit ())) "

　　

Python Day5 Dictionary