Worthwhile to reverse a dictionary

crc crc.214rin at no-mx.forums.yourdomain.com.au
Wed Jan 4 22:30:28 CET 2006


I assume your talking about building a new dictionary with the key and
value pair switched. I have seen no built in function to do this but I
have found a way to create another dictionary that is the inverse of
the first.

for example you have designed a dictionary such as

a={}
a['one']=1
a['two']=2
a['three']=3
a['four']=4

when your redy to build a revers dictionary you semply do the folowing
b={}
for x in a:
temp_idx=a[x]
b[temp_idx]=x

now you get
{'four': 4, 'three': 3, 'two': 2, 'one': 1}
for a

and 

{1: 'one', 2: 'two', 3: 'three', 4: 'four'}
for b


-- 
crc
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