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Why does Double.NaN==Double.NaN return false?
...
NaN is by definition not equal to any number including NaN. This is part of the IEEE 754 standard and implemented by the CPU/FPU. It is not something the JVM has to add any logic to support.
http://en.wikipedia.org/wiki/NaN
A...
Android accelerometer accuracy (Inertial navigation)
...
You get position by integrating the linear acceleration twice but the error is horrible. It is useless in practice.
Here is an explanation why (Google Tech Talk) at 23:20. I highly recommend this video.
It is not the accelerometer noise tha...
Immutable vs Mutable types
...'bar'
print s # foobar
The value of the variable changes, but it changes by changing what the variable refers to. A mutable type can change that way, and it can also change "in place".
Here is the difference.
x = something # immutable type
print x
func(x)
print x # prints the same thing
x = som...
Differences between Proxy and Decorator Pattern
...icts the client. Decorator does not. Proxy may restrict what a client does by controlling access to functionality; or it may restrict what a client knows by performing actions that are invisible and unknown to the client. Decorator does the opposite: it enhances what its delegate does in a way that ...
How to select multiple rows filled with constants?
...providable with an external variable):
SELECT level
FROM dual
CONNECT BY
level <= :n
in Oracle,
WITH q (l) AS
(
SELECT 1
UNION ALL
SELECT l + 1
FROM q
WHERE l < @n
)
SELECT l
FROM q
-- OPTION (MAXRECURSION 0)...
SQL Server NOLOCK and joins
...ll lock hints are propagated to all the tables and views that are accessed by the query plan, including tables and views referenced in a view. Also, SQL Server performs the corresponding lock consistency checks.
[SQL Server 2005]
In SQL Server 2005, all lock hints are propagated to all the tables an...
Why did my Git repo enter a detached HEAD state?
... 9fc9555312 Merge branch 'cc/shared-index-permbits'
it cannot detached by mistake a remote tracking branch
See:
C:\Users\vonc\arepo>git checkout origin/master
Note: switching to 'origin/master'.
You are in 'detached HEAD' state. You can look around, make experimental
changes and commit th...
How to terminate the script in JavaScript?
... exit( status ) {
// http://kevin.vanzonneveld.net
// + original by: Brett Zamir (http://brettz9.blogspot.com)
// + input by: Paul
// + bugfixed by: Hyam Singer (http://www.impact-computing.com/)
// + improved by: Philip Peterson
// + bugfixed by: Brett Zamir (ht...
Django: How to manage development and production settings?
... use a bootstrap script or a process manager to load the correct settings (by setting the environment), or just run it from your shell before starting Django: export DJANGO_SETTINGS_MODULE=myapp.production_settings.
Note that you can run this export at any time from a shell — it does not need to ...
What are the obj and bin folders (created by Visual Studio) used for?
...ntermediate object files and other transient data files that are generated by the compiler or build system during a build. The bin directory is the directory that final output binaries (and any dependencies or other deployable files) will be written to.
You can change the actual directories used fo...