With dictionary:
dictionary={1:'One', 2:'Two', 3:'Three', 4:'Four', 5:'Five'} and a list of known keys:
keys=[2, 4] What is the fastest shortest way to retrieve dictionary values?
The goal is to replace this code:
result=[] for key in dictionary: if not key in keys: continue result.append(dictionary[key]) Use list expression checking key existence
result=[dictionary[k] for k in keys if k in dictionary] Use a list comprehension:
[dictionary[k] for k in keys] 
print [dictionary[k] for k in dictionary.keys() if k in keys] Try this,
dictionary={1:'One', 2:'Two', 3:'Three', 4:'Four', 5:'Five'} result = [dictionary[i] for i in dictionary.keys()] print result Output: ['One', 'Two', 'Three', 'Four', 'Five'] 
EDITED you can use this
result = map(lambda x:x[1],dictionary.items()) Example
dictionary = {'x': 1, 'y': 2, 'z': 3} dictionary.items() >>[('y', 2), ('x', 1), ('z', 3)] result = map(lambda x:x[1],dictionary.items()) print result >>[2, 1, 3] 
dictionary.values() that does not limit the results to those for a known list of keys, as the OP requested.