This question’s answers are a community effort. Edit existing answers to improve this post. It is not currently accepting new answers or interactions. I wanted to test if a key exists in a dictionary before updating the value for the key. I wrote the following code: if ‘key1’ in dict.keys(): print “blah” else: print “boo” … Read more
How do I add a key to an existing dictionary? It doesn’t have an .add() method. 2 23
This question’s answers are a community effort. Edit existing answers to improve this post. It is not currently accepting new answers or interactions. I have a dictionary of values read from two fields in a database: a string field and a numeric field. The string field is unique, so that is the key of the … Read more
d = {‘x’: 1, ‘y’: 2, ‘z’: 3} for key in d: print(key, ‘corresponds to’, d[key]) How does Python recognize that it needs only to read the key from the dictionary? Is key a special keyword, or is it simply a variable? 1 15
I want to merge two dictionaries into a new dictionary. x = {‘a’: 1, ‘b’: 2} y = {‘b’: 10, ‘c’: 11} z = merge(x, y) >>> z {‘a’: 1, ‘b’: 10, ‘c’: 11} Using x.update(y) modifies x in-place instead of creating a new dictionary. I also want the last-one-wins conflict-handling of dict.update() as well. … Read more
I am relatively new to Java, and often find that I need to sort a Map<Key, Value> on the values. Since the values are not unique, I find myself converting the keySet into an array, and sorting that array through array sort with a custom comparator that sorts on the value associated with the key. … Read more
