dictionary

问题 I'm trying to create a pandas dataframe from a dictionary. The dictionary is set up as nvalues = {"y1": [1, 2, 3, 4], "y2": [5, 6, 7, 8], "y3": [a, b, c, d]} I would like the dataframe to include only "y1" and " y2" . So far I can accomplish this using df = pd.DataFrame.from_dict(nvalues) df.drop("y3", axis=1, inplace=True) I would like to know if it is possible to accomplish this without having df.drop() 回答1: You can specify columns in the DataFrame constructor: pd.DataFrame(nvalues, columns

问题 I'm trying to create a pandas dataframe from a dictionary. The dictionary is set up as nvalues = {"y1": [1, 2, 3, 4], "y2": [5, 6, 7, 8], "y3": [a, b, c, d]} I would like the dataframe to include only "y1" and " y2" . So far I can accomplish this using df = pd.DataFrame.from_dict(nvalues) df.drop("y3", axis=1, inplace=True) I would like to know if it is possible to accomplish this without having df.drop() 回答1: You can specify columns in the DataFrame constructor: pd.DataFrame(nvalues, columns

问题 I'm documenting some code, and I have a private HashMap. I'd like to specify information about what is expected from the key and value. Right now I have: /** * HashMap where key=word, value=part of speech */ private HashMap<String, String> dictionary; However, this seems hard to read, and also like it won't work well when I have something more complex like HashMap<String, HashMap<String, String>> What are best/common practices for documenting maps? 回答1: If you need a small javadoc, I suggest

问题 Say I have a dictionary built like this: d={0:1, 1:2, 2:3, 10:4, 11:5, 12:6, 100:7, 101:8, 102:9, 200:10, 201:11, 202:12} and I want to create a subdictionary d1 by slicing d in such a way that d1 contains the following keys: 0, 1, 2, 100, 101, 102 . The final output should be: d1={0:1, 1:2, 2:3, 100:7, 101:8, 102:9} Is there an efficient Pythonic way of doing this, given that my real dictionary contains over 2,000,000 items? I think this question applies to all cases where keys are integers,

问题 Brand new to python, Let's say I have a dict: kidshair = {'allkids':{'child1':{'hair':'blonde'}, 'child2':{'hair':'black'}, 'child3':{'hair':'red'}, 'child4':{'hair':'brown'}}} If child3 changes their hair colour regularly, I might want to write an application to speed up the data maintenance. In this example i'd use: kidshair['allkids']['child3']['hair'] = ... Is there any way to store this path as a variable so I can access it at my leasure? Obviously mypath = kidshair['allkids']['child3'][

问题 Brand new to python, Let's say I have a dict: kidshair = {'allkids':{'child1':{'hair':'blonde'}, 'child2':{'hair':'black'}, 'child3':{'hair':'red'}, 'child4':{'hair':'brown'}}} If child3 changes their hair colour regularly, I might want to write an application to speed up the data maintenance. In this example i'd use: kidshair['allkids']['child3']['hair'] = ... Is there any way to store this path as a variable so I can access it at my leasure? Obviously mypath = kidshair['allkids']['child3'][

问题 I would like to sort a list of objects, The structure is a Dictionary<Object, List<int>> items in the dictionary would be item_1, (2,2,3) item_2, (1,3,4) item_3, (2,3,4) item_4, (1,2) once the items are sorted they should appear as item_4, 1,2 item_2, 1,3,4 item_1, 2,2,3 item_3, 2,3,4 so, essentially I have to sort on the first item in the list, then the second item, then the 3rd items, what would be an easy way of implementing such a solution using linq 回答1: What you need is a custom

问题 I have a text file from Kaggle of Clash Royale stats. It's in a format of Python Dictionaries. I am struggling to find out how to read that into a file in a meaningful way. Curious what the best way is to do this. It's a fairly complex Dict with Lists. Original Dataset here: https://www.kaggle.com/s1m0n38/clash-royale-matches-dataset {'players': {'right': {'deck': [['Mega Minion', '9'], ['Electro Wizard', '3'], ['Arrows', '11'], ['Lightning', '5'], ['Tombstone', '9'], ['The Log', '2'], [

问题 I have a list of dictionaries in Python 3.5.2 that I am attempting to "deduplicate". All of the dictionaries are unique, but there is a specific key I would like to deduplicate on, keeping the dictionary with the most non-null values. For example, I have the following list of dictionaries: d1 = {"id":"a", "foo":"bar", "baz":"bat"} d2 = {"id":"b", "foo":"bar", "baz":None} d3 = {"id":"a", "foo":"bar", "baz":None} d4 = {"id":"b", "foo":"bar", "baz":"bat"} l = [d1, d2, d3, d4] I would like to

问题 I have a list of dictionaries in Python 3.5.2 that I am attempting to "deduplicate". All of the dictionaries are unique, but there is a specific key I would like to deduplicate on, keeping the dictionary with the most non-null values. For example, I have the following list of dictionaries: d1 = {"id":"a", "foo":"bar", "baz":"bat"} d2 = {"id":"b", "foo":"bar", "baz":None} d3 = {"id":"a", "foo":"bar", "baz":None} d4 = {"id":"b", "foo":"bar", "baz":"bat"} l = [d1, d2, d3, d4] I would like to