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Group by in LINQ
... new { PersonId = key.Id, PersonName = key.Name, PersonCount = g.Count()}) and you will get all the people that occur with an Id, Name, and a number of occurrences for each person.
– Chris
Aug 6 '15 at 21:40
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How to copy a file to multiple directories using the gnu cp command
...it possible to copy a single file to multiple directories using the cp command ?
22 Answers
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How can I check if my python object is a number? [duplicate]
...0, 0.0, 0j, decimal.Decimal(0))]
[True, True, True, True]
This uses ABCs and will work for all built-in number-like classes, and also for all third-party classes if they are worth their salt (registered as subclasses of the Number ABC).
However, in many cases you shouldn't worry about checking t...
Is there a simple way to delete a list element by value?
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edited Mar 23 at 12:07
Andrey Semakin
64888 silver badges2525 bronze badges
answered May 8 '10 at 7:56
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Programmatically creating Markdown tables in R with KnitR
I am just starting to learn about KnitR and the use of Markdown in generating R documents and reports. This looks to be perfect for a lot of the day to day reporting that I have to do with my job. However, one thing that I'm not seeing is an easy way to print data frames and tables using Markdown fo...
How to convert a char array to a string?
...a char array is pretty straightorward using the c_str function of string and then doing strcpy . However, how to do the opposite?
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How to sum up elements of a C++ vector?
...tor.begin(); it != vector.end(); ++it)
sum_of_elems += *it;
Using a standard algorithm:
#include <numeric>
sum_of_elems = std::accumulate(vector.begin(), vector.end(), 0);
Important Note: The last argument's type is used not just for the initial value, but for the type of the resu...
data.table vs dplyr: can one do something well the other can't or does poorly?
...able , not so much with dplyr . I've read through some dplyr vignettes and examples that have popped up on SO, and so far my conclusions are that:
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Identify if a string is a number
... Function will return true if I pass string as "-123" or "+123". I Understand that integer has positive and negative values. But If this string is coming from user entered textbox then it should return false.
– user2323308
Aug 28 '13 at 13:58
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How to use a switch case 'or' in PHP
...icated" statements, eg: to test if a value is "greater than 3", "between 4 and 6", etc. If you need to do something like that, stick to using if statements, or if there's a particularly strong need for switch then it's possible to use it back to front:
switch (true) {
case ($value > 3) :
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