Use dictionary comprehensions. They work pretty much the same as list comprehensions and generator expressions. filtered_dict = {key: value for key, value in old_dict.iteritems() if value > 90} More on reddit.com

You don’t want a dictionary comprehension, you want a list comprehension. You can’t return in a list comprehension, but you can return a list comprehension. Lambdas don’t even have returns. lambda d: [key[-2:] for key in d.keys()] You could also do the following, but I think the first is more explicit. lambda d : [key[-2:] for key in d] More on reddit.com

How can I filter items in a Python dictionary where the keys contain a specific substring? I’m a C programmer transitioning to Python, and I’m familiar with how this can be done in C. In C, I would iterate over the dictionary (or hash map) and check if the key contains a specific substring. More on community.testmuai.com

I need to learn how to filter by key/value for several different conditions and then create a new key/value based on the filtered results In general, this will probably involve looping over your keys/values, applying a condition, and creating a new dict from only those items which pass the condition. If your conditions are simple, a dict comprehension is a good way to go. Something like the following, where I create a dict, then filter the keys/value to retain only those items with even-numbered keys: >>> d = dict(enumerate('abcde')) >>> d {0: 'a', 1: 'b', 2: 'c', 3: 'd', 4: 'e'} >>> new_d = {k : v for k, v in d.items() if k % 2 == 0} >>> new_d {0: 'a', 2: 'c', 4: 'e'} For more complex conditions, comprehensions can get long and unwieldy, so vanilla for loops are probably preferred. For example, when filtering keys/values to retain only those items with even-numbered keys AND vowels as values: >>> d = dict(enumerate('abcde')) >>> vowels = 'aeiou' >>> new_d = {} >>> for k, v in d.items(): ... if (v in vowels) and (k % 2 == 0): ... new_d[k] = v ... >>> new_d {0: 'a', 4: 'e'} I need to learn more about dictionaries and how they work to access and calculate the data for my work. I think I understand the basics, but when I get to slightly more complex scenarios I get stuck. To master dicts, spend some time looking at the output of dir(dict) to see which methods are available. Read up on and play around with each because they all have their time and place. Dicts are incredibly useful and powerful when used responsibly. Is there any articles/courses/videos that explain how to use dictionaries in more depth than the basics. If you want an actual article with some example code, these sites generally tend to be quite good in my experience: https://realpython.com/python-dicts/ https://www.programiz.com/python-programming/dictionary https://www.geeksforgeeks.org/python-dictionary/ then perform statistical analysis on them Feel free to ask any stats questions here if they are relevant, though I gather the bulk of your struggles just concern how to use data stored ini dictionaries, not how to do stats with Python. Those are two very different things. More on reddit.com