Dictionary class
1. Generation:
. A description:
Dictionary is a collection of key-value pairs, key-value pair: the key is the data index extension
. B generation method:
Use} or {dict ()
= {A ' A ' =. 1, ' B ' = 2, ' C ' =. 3 }
A = dict (A =. 1, B = 2, C =. 3 )
A = {} # can be used to generate an empty dictionary
Note that: {} generated default dictionary can not be used to generate a set of
2. dictionary class methods:
. 1 del d [k] # remove the key and the corresponding value 2 k in d # determines whether k is the d key . 3 d.key () # List all the key . 4 d.values () # list all value . 5 d.items () # List all the key and the corresponding value . 6 d.get (K, <default>) # obtaining the key corresponding to the value, if the key does not exist <default> is returned . 7 d.pop ( K, <default>) # obtain a value corresponding to the key and delete, if the key does not exist <default> is returned . 8 d.popitem () returns a tuple # remove the last key-value pair dict