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Is it possible to Pivot data using LINQ?
...=> c.OrderDate.Month == 3).Sum(c => c.Qty)
});
GroupBy in Linq does not work the same as SQL. In SQL, you get the key and aggregates (row/column shape). In Linq, you get the key and any elements as children of the key (hierarchical shape). To pivot, you must project the hierarchy back...
How to request Administrator access inside a batch file
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This script does the trick! Just paste it into the top of your bat file. If you want to review the output of your script, add a "pause" command at the bottom of your batch file.
UPDATE: This script is now slightly edited to support comm...
Adding external library into Qt Creator project
...efix). Of course, if you are including a Windows specific lib, this really doesn't matter.
In case you want to store your lib files in the project directory, you can reference them with the $$_PRO_FILE_PWD_ variable, e.g.:
LIBS += -L"$$_PRO_FILE_PWD_/3rdparty/libs/" -lpsapi
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Why am I getting an OPTIONS request instead of a GET request?
it does an OPTIONS request to that URL, and then the callback is never called with anything.
10 Answers
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Remove all occurrences of a value from a list?
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This doesn't modify the original list but returns a new list.
– John Y
Jul 21 '09 at 3:20
6
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Find the index of a dict within a list, by matching the dict's value
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first() does sound better. You could always try/except the StopIteration and raise ValueError so the caller has consistency. Alternatively set next()'s default to -1.
– Ben Hoyt
Dec 8 '10 at 21:...
Detecting an undefined object property
...operty value is the special value `undefined`");
}
To check if an object does not actually have such a property, and will therefore return undefined by default when you try and access it:
if(!o.hasOwnProperty('myProperty')) {
alert("myProperty does not exist");
}
To check if the value associa...
What is the concept of erasure in generics in Java?
...t;T> parameter to a constructor (or generic method) simply because Java doesn't retain that information. Look at EnumSet.allOf for example - the generic type argument to the method should be enough; why do I need to specify a "normal" argument as well? Answer: type erasure. This sort of thing pol...
How to find out if an item is present in a std::vector?
...non-members. And there is a widespread school of thought that if something does not have to be a member, or when it does not give any advantage when implemented as a member, than it should not be a member; std::vector<>::find() would not give any advantage, nor is it needed, therefore, no, it ...
Why do we need break after case statements?
Why doesn't the compiler automatically put break statements after each code block in the switch? Is it for historical reasons? When would you want multiple code blocks to execute?
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