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Double not (!!) operator in PHP
...ings or empty arrays) you will get the boolean value FALSE.
It is functionally equivalent to a cast to boolean:
return (bool)$row;
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Grouped LIMIT in PostgreSQL: show the first N rows for each group?
... For those who works with like millions rows and seeks for really performant way to do this - poshest's answer is the way to go. Just dont forget to spice ti up with proper indexing.
– Diligent Key Presser
Jun 20 '19 at 8:46
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Show an image preview before upload
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HTML5 comes with File API spec, which allows you to create applications that let the user interact with files locally; That means you can load files and render them in the browser without actually having to upload the files. Part of the File API is the FileReader...
Can you resolve an angularjs promise before you return it?
...Nizet's Plunkr but refactored to work within the context of what was originally asked (i.e. a function call to service) and actually on site.
Inside the service...
function getSomething(id) {
// There will always be a promise so always declare it.
var deferred = $q.defer();
if (Cache[i...
Is it possible to specify your own distance function using scikit-learn K-Means Clustering?
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Here's a small kmeans that uses any of the 20-odd distances in
scipy.spatial.distance, or a user function.
Comments would be welcome (this has had only one user so far, not enough);
in particular, what are your N, dim, k, metric ?
#!/u...
Is there any difference between “foo is None” and “foo == None”?
... Hmmm, I think your link changed, unless you were interested in how to call external functions from python
– Pat
May 4 '12 at 20:39
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Run java jar file on a server as background process
...on
[Service]
ExecStart=/usr/bin/java -jar /web/server.jar
User=user
[Install]
WantedBy=multi-user.target
Step 4:
Run your service
as super user
$ systemctl start whatever_you_want.service # starts the service
$ systemctl enable whatever_you_want.service # auto starts the service
$ systemctl ...
Gradle to execute Java class (without modifying build.gradle)
...ATE
:classes
:execute
I am BOO!
mainClass is a property passed in dynamically at command line. classpath is set to pickup the latest classes.
If you do not pass in the mainClass property, both of the approaches fail as expected.
$ gradle execute
FAILURE: Build failed with an exception.
* Whe...
How to share my Docker-Image without using the Docker-Hub?
...ers are stored by default under /var/lib/docker. While you could (theoretically) cherry pick files from there and install it in a different docker server, is probably a bad idea to play with the internal representation used by Docker.
When you push your image, these layers are sent to the registry ...
Combining Multiple Commits Into One Prior To Push
...its at once. Many times, you may want to break your work down into a few small, logical commits, but only push them up once you feel like the whole series is ready. Or you might be making several commits locally while disconnected, and you push them all once you're connected again. There's no reason...