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Why are quaternions used for rotations?
...s (despite the bizarre story that's occasionally told about Hamilton/Gibbs/etc). Physics requires that our descriptions have good analytic behavior (this has a precisely defined meaning, but in some rather technical ways that go far beyond what's taught in normal intro classes, so I won't go into an...
Android activity life cycle - what are all these methods for?
...do
all of your normal static set up: create views, bind data to lists,
etc. This method also provides you with a Bundle containing the
activity's previously frozen state, if there was one. Always followed
by onStart().
onRestart():
Called after your activity has been stopped, prior to ...
Java Interfaces/Implementation naming convention [duplicate]
...a Type. Then you have DumpTruck, TransferTruck, WreckerTruck, CementTruck, etc that implement Truck.
When you are using the Interface in place of a sub-class you just cast it to Truck. As in List<Truck>. Putting I in front is just Hungarian style notation tautology that adds nothing but more...
Simple way to transpose columns and rows in SQL?
...out having to know anything about the query itself, or the columns, tables etc it is extracting info from. Something like: (TRANSPOSE (SELECT......)) In my example given above, imagine that the first table is a result set generated from a very complex query involving multiple tables, unions, pivot...
What is Castle Windsor, and why should I care?
...ssemblies. You can specify lifecycles like singleton or per-http-request, etc. Keep going - it will change your work.
– Matt Hinze
Sep 24 '08 at 17:19
6
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Technically, why are processes in Erlang more efficient than OS threads?
...he entire CPU state (normal, SSE and FPU registers, address space mapping, etc.).
Erlang processes use dynamically allocated stacks, which start very small and grow as necessary. This permits the spawning of many thousands — even millions — of Erlang processes without sucking up all available RA...
List files by last edited date
...most/some/? linux distributions. Some define it as an alias ll='ls -l' in /etc/bash.bashrc or /etc/.bashrc. Thus it may not work and it may not exists on OPs system. Use ls -l -Rt at least, as ls is a standard command as defined by posix. Or specify you meant alias ll='ls -l'; ll -Rt.
...
What specifically are wall-clock-time, user-cpu-time, and system-cpu-time in UNIX?
...what you think. System calls, which include I/O calls such as read, write, etc. are executed by jumping into kernel code and executing that.
If wall clock time < CPU time, then you're executing a program in parallel. If wall clock time > CPU time, you're waiting for disk, network or other dev...
Give all the permissions to a user on a DB
...ll set the privileges on all relations: tables, views, indexes, sequences, etc. If you want to restrict that, filter on pg_class.relkind. See the pg_class docs for details.
You should run this function as superuser and as regular as your application requires. An option would be to package this in a...
JavaScript ternary operator example with functions
...e if (something_else)
{
//40 more lines here
}
else if (another_one) /etc, etc
{
...
Less good:
this > that ? testFucntion() ? thirdFunction() ? imlost() : whathappuh() : lostinsyntax() : thisisprobablybrokennow() ? //I'm lost in my own (awful) example by now.
//Not complete... or for...