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Simple Pivot Table to Count Unique Values
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UPDATE: You can do this now automatically with Excel 2013. I've created this as a new answer because my previous answer actually solves a slightly different problem.
If you have that version, then select your data to create a pivot table, and when you create yo...
Get first n characters of a string
...}
Update 3:
It's been a while since I wrote this answer and I don't actually use this code any more. I prefer this function which prevents breaking the string in the middle of a word using the wordwrap function:
function truncate($string,$length=100,$append="…") {
$string = trim($st...
How to express a NOT IN query with ActiveRecord/Rails?
.... It would still break on nil, but I find that the array you pass in is usually generated by a filter that will return [] at the very least and never nil. I recommend checking out Squeel, a DSL on top of Active Record. Then you could do: Topic.where{id.not_in actions}, nil/empty/or otherwise.
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Insert/Update Many to Many Entity Framework . How do I do it?
...ject and cannot seem to work out how to insert or update. I have build a small project just to see how it should be coded.
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How to sort an ArrayList?
...t the runtime characteristics of reverse, but sorting descending could actually be faster then sorting ascending and then reversing. Moreover, using a List implementation that supports Comparator as constructor argument (thus keeping it invariant) would ensure the list is sorted at all times.
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Which parts of Real World Haskell are now obsolete or considered bad practice?
...move return from Monad, so the Monad instance in Real World Haskell will really be out of sync with the real world.
That being said, it's still a useful resource for general guidelines. But keep in mind that many libraries changed since its release.
Something you can read along while reading RWH i...
When is memoization automatic in GHC Haskell?
...2' = \n -> (!!) (filter odd [1..]) n
(Note: The Haskell 98 report actually describes a left operator section like (a %) as equivalent to \b -> (%) a b, but GHC desugars it to (%) a. These are technically different because they can be distinguished by seq. I think I might have submitted a G...
How is the java memory pool divided?
...ap memory
The heap memory is the runtime data area from which the Java VM allocates memory for all class instances and arrays. The heap may be of a fixed or variable size. The garbage collector is an automatic memory management system that reclaims heap memory for objects.
Eden Space: The pool fr...
Why is (object)0 == (object)0 different from ((object)0).Equals((object)0)?
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The reason the calls behave different is they bind to very different methods.
The == case will bind to the static reference equality operator. There are 2 independent boxed int values created hence they are not the same reference.
In th...
What is NODE_ENV and how to use it in Express?
...ment variable and do different things based on the value. NODE_ENV specifically is used (by convention) to state whether a particular environment is a production or a development environment. A common use-case is running additional debugging or logging code if running in a development environment.
A...