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Last iteration of enhanced for loop in java
...thing about this is that it will work with any Iterable - you can't always index things. (The "add the comma and then remove it at the end" is a nice suggestion when you're really using StringBuilder - but it doesn't work for things like writing to streams. It's possibly the best approach for this e...
Null coalescing in powershell
...becomes one of the following (depending on preference):
$s = if ($myval -eq $null) { "new value" } else { $myval }
$s = if ($myval -ne $null) { $myval } else { "new value" }
or depending on what $myval might contain you could use:
$s = if ($myval) { $myval } else { "new value" }
and the second...
What's the status of multicore programming in Haskell?
... Simon Marlow -- more control over pure parallelism than strategies/par/pseq.
Cloud Haskell: Erlang-style message passing between distributed Haskell nodes.
Parallel Haskell: Embracing Diversity, a talk by SPJ.
Real time edge detection in parallel Haskell
Parallel Haskell Digest: news on parallel Ha...
Transposing a 2D-array in JavaScript
...
array[0].map((_, colIndex) => array.map(row => row[colIndex]));
map calls a provided callback function once for each element in an array, in order, and constructs a new array from the results. callback is invoked only for indexes of t...
belongs_to through associations
...n. You're better off caching the question_id on Choice and adding a unique index to the table (especially because validates_uniqueness_of is prone to race conditions).
If you're paranoid, add a custom validation to Choice that confirms that the answer's question_id matches, but it sounds like the e...
jar not loaded. See Servlet Spec 2.3, section 9.7.2. Offending class: javax/servlet/Servlet.class
...ommand line useful in tracking down the offending jar file. it creates an index of all the class files in all the jars in the folder. Execute from within the lib folder of your deployed app, then search the index.txt file for the offending class.
for /r %X in (*.jar) do (echo %X & jar -tf %X)...
How to store arrays in MySQL?
... will not clutter the row containing the linked item. And the database can index those rows. Arrays typically aren't indexed.
If you don't need relational databases, you can use e.g. a key-value store.
Read about database normalization, please. The golden rule is "[Every] non-key [attribute] must ...
.NET data structures: ArrayList, List, HashTable, Dictionary, SortedList, SortedDictionary — Speed,
...re a fixed size collection that you can change the value stored at a given index.
SortedDictionary is an IDictionary that is sorted based on the keys.
SortedList is an IDictionary that is sorted based on a required IComparer.
So, the IDictionary implementations (those supporting KeyValuePairs) ar...
What is state-of-the-art for text rendering in OpenGL as of version 4.1? [closed]
...nates and only differ in the r coordinate, which is equal to the character index to render.
But like with the other techniques, the expected gains are marginal at the cost of being incompatible with previous generation hardware.
There is a handy tool by Jonathan Dummer for generating distance textu...
How to drop columns by name in a data frame
...
You should use either indexing or the subset function. For example :
R> df <- data.frame(x=1:5, y=2:6, z=3:7, u=4:8)
R> df
x y z u
1 1 2 3 4
2 2 3 4 5
3 3 4 5 6
4 4 5 6 7
5 5 6 7 8
Then you can use the which function and the - operat...