Operations on Dictionaries
Dictionaries provide a mapping between names and objects. You can apply the following operations to dictionaries:
Operation | Description |
---|---|
x = d[k] | Indexing by key |
d[k] = x | Assignment by key |
del d[k] | Deletes an item by key |
len(d) | Number of items in the dictionary |
Key values can be any immutable object, such as strings, numbers, and tuples. In addition, dictionary keys can be specified as a comma-separated list of values, like this:
d = { } d[1,2,3] = "foo" d[1,0,3] = "bar"
In this case, the key values represent a tuple, making the preceding assignments identical to the following:
d[(1,2,3)] = "foo" d[(1,0,3)] = "bar"
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