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Where can I learn jQuery? Is it worth it?
...articular need. First, come up with a short list of criteria to guide your selection and evaluation process.
Then, check out a high level framework comparison/reviews somewhere like Wikipedia, select a few that fit your criteria and interest you. Test them out to see how they work for you. Most, i...
Increment a database field by 1
...complex depending on your specific needs:
INSERT into mytable (logins)
SELECT max(logins) + 1
FROM mytable
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Delete text in between HTML tags in vim?
... Also vat (or vit), followed by repeated at (or it) to progressively select surrounding tags . (Or v2at, etc). Then d to delete (etc).
– Joe Freeman
Feb 16 '17 at 17:09
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In c# what does 'where T : class' mean?
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Voted down, it must not be selected as answer.
– Jonathan
Aug 22 at 17:30
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Why is lazy evaluation useful?
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@Viclib A selection algorithm for finding the top k elements out of n is O(n + k log k). When you implement quicksort in a lazy language, and only evaluate it far enough to determine the first k elements (stopping evaluation after), i...
Quicksort vs heapsort
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For any deterministic, constant time pivot selection strategy, you can find an array that produces the O(n^2) worst case. It's not enough to eliminate just the minimum. You have to reliably chose pivots that are within a certain pecrentile band.
–...
C# LINQ find duplicates in List
...y(x => x)
.Where(g => g.Count() > 1)
.Select(y => y.Key)
.ToList();
If you want to know how many times the elements are repeated, you can use:
var query = lst.GroupBy(x => x)
.Where(g => g.Count() > 1)
.Sel...
Why isn't SQL ANSI-92 standard better adopted over ANSI-89?
...shion. The "best" way to break is by compilation error. For example if you SELECT * somewhere, the addition of a column could fail to compile. The next best way to fail would be a run time error. It's worse because your users may see it, but it still gives you a nice warning that you've broken somet...
How to join (merge) data frames (inner, outer, left, right)
...s these operations in SQL.
library(sqldf)
## inner join
df3 <- sqldf("SELECT CustomerId, Product, State
FROM df1
JOIN df2 USING(CustomerID)")
## left join (substitute 'right' for right join)
df4 <- sqldf("SELECT CustomerId, Product, State
FROM df1...
Why would you use Expression rather than Func?
...y. Ie. you need database.data.Where(i => i.Id > 0) to be executed as SELECT FROM [data] WHERE [id] > 0. If you just pass in a Func, you've put blinders on your driver and all it can do is SELECT * and then once it's loaded all of that data into memory, iterate through each and filter out ev...