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LINQ's Distinct() on a particular property
...m and pick a winner out of the group.
List<Person> distinctPeople = allPeople
.GroupBy(p => p.PersonId)
.Select(g => g.First())
.ToList();
If you want to define groups on multiple properties, here's how:
List<Person> distinctPeople = allPeople
.GroupBy(p => new {p.Pe...
How to do date/time comparison
...Go? I have to sort data based on date and time - independently. So I might allow an object that occurs within a range of dates so long as it also occurs within a range of times. In this model, I could not simply just select the oldest date, youngest time/latest date, latest time and Unix() seconds c...
Where is shared_ptr?
...rking). Simply stating std , tr1 and <memory> is not helping at all! I have downloaded boosts and all but still it doesn't show up! Can someone help me by telling exactly where to find it?
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Selecting and manipulating CSS pseudo-elements such as ::before and ::after using jQuery
... using jQuery, for slightly shorter code.
Pros: any string can be dynamically inserted into the style
Cons: original styles aren't altered, just overridden; repeated (ab)use can make the DOM grow arbitrarily large
3) Alter a different DOM attribute
You can also to use attr() in your CSS to re...
Android: How to put an Enum in a Bundle?
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Enums are Serializable so there is no issue.
Given the following enum:
enum YourEnum {
TYPE1,
TYPE2
}
Bundle:
// put
bundle.putSerializable("key", YourEnum.TYPE1);
// get
YourEnum yourenum = (YourEnum) bundle.get("key");
Intent:
// put
intent.putExtra("key", yourEnu...
Should I declare Jackson's ObjectMapper as a static field?
...hey are fully immutable, thread-safe, meaning that it is not even theoretically possible to cause thread-safety issues (which can occur with ObjectMapper if code tries to re-configure instance).
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How can I get the list of a columns in a table for a SQLite database?
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What you're looking for is called the data dictionary. In sqlite a list of all tables can be found by querying sqlite_master table (or view?)
sqlite> create table people (first_name varchar, last_name varchar, email_address varchar);
sqlite> sel...
LINQ - Left Join, Group By, and Count
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.Count() will generate COUNT(*) which will count all the rows in that group, by the way.
– Mehrdad Afshari
Mar 29 '09 at 22:47
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How to format a number as percentage in R?
One of the things that used to perplex me as a newby to R was how to format a number as a percentage for printing.
10 Answe...
How do I grep for all non-ASCII characters?
... Homebrew's dupes library (enable using brew tap homebrew/dupes): brew install grep
– Bastiaan M. van de Weerd
Oct 22 '12 at 10:03
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