Merging dictionaries in C#

What's the best way to merge 2 or more dictionaries (Dictionary<T1,T2>) in C#? (3.0 features like LINQ are fine). I'm thinking of a method signature along the lines of: public static...

How can I add new keys to a dictionary?

Is it possible to add a key to a Python dictionary after it has been created? It doesn't seem to have an .add() method.

How to use a dot "." to access members of dictionary?

How do I make Python dictionary members accessible via a dot "."? For example, instead of writing mydict['val'], I'd like to write mydict.val. Also I'd like to access nested dicts this way. For...

Dictionary returning a default value if the key does not exist

I find myself using the current pattern quite often in my code nowadays var dictionary = new Dictionary<type, IList<othertype>>(); // Add stuff to dictionary var somethingElse =...

Django Backend-neutral DictCursor

Is there any way to get a backend-neutral dictionary cursor in Django? This would be a cursor that is a dict rather than a tuple. I am forced to use Oracle for the school project I'm working...

What use does the JavaScript forEach method have (that map can't do)?

The only difference I see in map and foreach is that map is returning an array and forEach is not. However, I don't even understand the last line of the forEach method "func.call(scope, this[i],...

Iterating over dictionaries using 'for' loops

I am a bit puzzled by the following code: d = {'x': 1, 'y': 2, 'z': 3} for key in d: print (key, 'corresponds to', d[key]) What I don't understand is the key portion. How does Python...

Return None if Dictionary key is not available

I need a way to get a dictionary value if its key exists, or simply return None, if it does not. However, Python raises a KeyError exception if you search for a key that does not exist. I know...

Isometric game data structure and rendering

I'm starting development of a 2d isometric(tiled, roguelike) game and I'm brainstorming which kind of data structure I would use to store runtime data like tiles and entities, but I don't want to...

How can I declare a custom sort function on std::map declaration?

The container std::map always sorts keys based on their value. Is it possible to make it sort, for example, on the number of bits set upon declaration? I have a function for counting set...

python pandas dataframe columns convert to dict key and value

I have a pandas data frame with multiple columns and I would like to construct a dict from two columns: one as the dict's keys and the other as the dict's values. How can I do that? Dataframe: ...

Python: Collections.Counter vs defaultdict(int)

Suppose I have some data that looks like the following. Lucy = 1 Bob = 5 Jim = 40 Susan = 6 Lucy = 2 Bob = 30 Harold = 6 I want to combine: remove duplicate keys, and add the values for these...

storing and retrieving images in dictionary - python

Can anyone tell me how to store images in python dictionary (dict), and how to retrieve images from the dictionary based on the key value ?

Assert that two dictionaries are almost equal

I am trying to assert that two dictionaries are almost equal, but I can't seem to do that. Here is an example: >>> import nose.tools as nt >>> nt.assert_dict_equal({'a' : 12.4}, {'a' : 5.6 +...

Python Json loads() returning string instead of dictionary?

I'm trying to do some simple JSON parsing using Python 3's built in JSON module, and from reading a bunch of other questions on SO and googling, it seems this is supposed to be pretty...

How to convert a Swift object to a dictionary

I'm relatively new to iOS programming. However, I would have assumed that Swift would have an automated way of converting objects to JSON and vice versa. That being said, I have found several...

Dict merge in a dict comprehension

In python 3.5, we can merge dicts by using double-splat unpacking >>> d1 = {1: 'one', 2: 'two'} >>> d2 = {3: 'three'} >>> {**d1, **d2} {1: 'one', 2: 'two', 3: 'three'} Cool. It doesn't seem to...

Python: coursera assignments - Dictionary chapter

I'm trying to solve the assignments from coursera - Python. Write a program to read through the mbox-short.txt and figure out who has the sent the greatest number of mail messages. The program...

TypeError 'set' object does not support item assignment

I need to know why it won't let me increase the value of the assignment by 1: keywords = {'states' : 0, 'observations' : 1, 'transition_probability' : 2, 'emission_probability' : 3} keylines =...

Python update a key in dict if it doesn't exist

I want to insert a key-value pair into dict if key not in dict.keys(). Basically I could do it with: if key not in d.keys(): d[key] = value But is there a better way? Or what's the pythonic...

How to print dictionary values line by line in Python?

This is my dictionary {'www.pic2fly.com/Weather+Of+Bahawalpur.html': ['https://tse1.mm.bing.net/th? id=OIP.RsEykDoK1xxg2zivHYW7WwEsC5&pid=Api'], 'panoramio.com/photo/84118355': ...

nltk words corpus does not contain "okay"?

The NLTK word corpus does not have the phrase "okay", "ok", "Okay"? > from nltk.corpus import words > words.words().__contains__("check") > True > words.words().__contains__("okay") > False >...

What is the difference between Tuple, Dictionary and List in C#?

This question already has an answer here. I was trying to use Tuple in my application. So I want to differentiate a Tuple, Dictionary and List. Dictionary<int, string> dic = new Dictionary<int,...

Converting a dictionary of dictionaries to a List of dictionaries

I have a dictionary of dictionaries.Is there any possible way to convert it to a list of dictionaries? And if not, then how is the filter() method applied to filter data in a dictionary of dictionaries?

geom_sf size argument doesn't work when size < 1

Question: I'm trying to create a map of U.S. states/counties with the sf package and geom_sf() from ggplot2, but I can't get the size argument for polygon border line width in geom_sf() to...

How to import all Dart files from a Directory?

I am new to dart so please bear with me if this is really bad question. I am developing an app using flutter, and I have one question. I have many screens in my app, like About the App, Homepage,...

Why does my python program give run time error on Kattis interpretor?

When I submit this file to Kattis I get a Run Time Error with no further explanation. It seems like simple enough code, but maybe I'm just missing something. It runs on my python 3 interpreter....

Is there a way to serialize a map in Kotlinx-Serialization

I'm using Kotlin 1.3.10 (and bound to this version) and Kotlinx-Serialization 0.13 and I'm having trouble with serializing a map in Kotlinx-Serialization. I have the following...

Write a program to read through the mbox-short.txt and figure out the distribution by hour of the day for each of the messages

10.2 Write a program to read through the mbox-short.txt and figure out the distribution by hour of the day for each of the messages. You can pull the hour out from the 'From ' line by finding the...

Python - Itterate down dictionairy - move down tree conditionally

I have a some python code below that walk down a tree but I want it to work down a tree checking taking some paths conditioally based on values. I want to get the LandedPrice for branches of tree...

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