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Before posting, I have already gone through Access an arbitrary element in a dictionary in Python, butI'm uncertain about this.
I have a long dictionary and I've to get the values of its first and last keys. I can use dict[dict.keys()[0]] and dict[dict.keys()[-1]] to get the first and last elements, but since the key:value pairs are outputted in a random form(as in the positioning of the key:value pairs is random), will the solution provided in this link always work?
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Accessing Elements from DictionaryKeys can be used either inside square brackets [] or with the get() method. If we use the square brackets [] , KeyError is raised in case a key is not found in the dictionary. On the other hand, the get() method returns None if the key is not found.
Get first value in a dictionary using item() item() function of dictionary returns a view of all dictionary in form a sequence of all key-value pairs. From this sequence select the first key-value pair and from that select first value.
Also called headword, guide word. a word printed at the top of a page in a dictionary or other reference book to indicate the first or last entry or article on that page.
Use an OrderedDict, because a normal dictionary doesn't preserve the insertion order of its elements when traversing it. Here's how:
# import the right class from collections import OrderedDict # create and fill the dictionary d = OrderedDict() d['first'] = 1 d['second'] = 2 d['third'] = 3 # retrieve key/value pairs els = list(d.items()) # explicitly convert to a list, in case it's Python 3.x # get first inserted element els[0] => ('first', 1) # get last inserted element els[-1] => ('third', 3) If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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