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How to get index using LINQ? [duplicate]
...not.
Therefore, LINQ does not have an IndexOf method.
However, you can write one yourself:
///<summary>Finds the index of the first item matching an expression in an enumerable.</summary>
///<param name="items">The enumerable to search.</param>
///<param name="predicate...
Algorithm to detect corners of paper sheet in photo
...er this year. This was my first ever coding project, and kinda ended in a bit of a rush, so the code needs some errr...decoding...
I'll give a few tips from what I've seen you doing already, and then sort my code on my day off tomorrow.
First tip, OpenCV and python are awesome, move to them as soo...
NSOperation vs Grand Central Dispatch
...g GCD.
In general, you should use the highest level of abstraction that suits your needs. This means that you should usually use NSOperationQueue instead of GCD, unless you need to do something that NSOperationQueue doesn't support.
Note that NSOperationQueue isn't a "dumbed-down" version of GCD; ...
How to calculate date difference in JavaScript?
... in days, hours, minutes, seconds, milliseconds, nanoseconds. How can I do it?
18 Answers
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The cast to value type 'Int32' failed because the materialized value is null
...nulls in different places. ...DefaultIfEmpty(0).Sum(0) can help in this (quite simple) case, where there might be no elements and sql's SUM returns null whereas c# expect 0.
A more general approach is to use ?? which will be translated to COALESCE whenever there is a risk that the generated SQL ret...
Unzipping files in Python
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import zipfile
with zipfile.ZipFile(path_to_zip_file, 'r') as zip_ref:
zip_ref.extractall(directory_to_extract_to)
That's pretty much it!
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Convert Set to List without creating new List
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You can use the List.addAll() method. It accepts a Collection as an argument, and your set is a Collection.
List<String> mainList = new ArrayList<String>();
mainList.addAll(set);
EDIT: as respond to the edit of the question.
It is easy to see that ...
MongoDB and “joins” [duplicate]
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It's no join since the relationship will only be evaluated when needed. A join (in a SQL database) on the other hand will resolve relationships and return them as if they were a single table (you "join two tables into one").
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receiving error: 'Error: SSL Error: SELF_SIGNED_CERT_IN_CHAIN' while using npm
... not https though & am wondering if that could have resulted in the issue with npm/unsigned certs). The error pops up once npm tries to resolve the ' https://registry.npmjs.org ' URL. Is there anyway I can ignore the error or perhaps locate/add the cert to a trusted store in order to continue usin...
How to add external library in IntelliJ IDEA?
I am trying to add external library (places it in the /libs directory) to my project. When I try to use the methods from that library, I see that they are in red color which means that the library is not recognized. When I click Ctrl+B, I get a message "Cannot find declaration to go to".
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