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Grouping functions (tapply, by, aggregate) and the *apply family
...of the *apply family is covered by the extremely popular plyr package, the base functions remain useful and worth knowing.
This answer is intended to act as a sort of signpost for new useRs to help direct them to the correct *apply function for their particular problem. Note, this is not intended t...
Can you center a Button in RelativeLayout?
...="true"
which alignes the child view to the parent view. The "center" is based on the axis of the alignement you have chosen:
left/right -> vertical
top/bottom -> horizontal
Setting the gravity of childs/content inside the view:
android:gravity="center"
is centering the child inside t...
Java using enum with switch statement
... the enum name in String.
.ordinal() allow you to get the integer value, 0-based.
You can attach other value parameters with each enum.
and, of course, switch enabled.
enum with value parameters:
enum StateEnum {
UNDEFINED_POLL ( 1 * 1000L, 4 * 1000L),
SUPPORT_POLL (...
Pass ruby script file to rails console
...2:-$PWD}')";}
Example:
cd ~/rails_project/app/helpers
rr my_script.rb
Based on @moritz's answer here. I changed it, since the working directory for File.read is the Rails project root.
I know this is some serious heresy, using python to help a ruby script. But I couldn't find a relpath method ...
How to share my Docker-Image without using the Docker-Hub?
...
Based on this blog, one could share a docker image without a docker registry by executing:
docker save --output latestversion-1.0.0.tar dockerregistry/latestversion:1.0.0
Once this command has been completed, one could cop...
Clear Application's Data Programmatically
...ackoverflow.com/a/29197259/1815624
Here is the resulting combined source based answer
private void clearAppData() {
try {
// clearing app data
if (Build.VERSION_CODES.KITKAT <= Build.VERSION.SDK_INT) {
((ActivityManager)getSystemService(ACTIVITY_SERVICE)).clearA...
IntelliJ IDEA generating serialVersionUID
...y do what the JVM does when the ID is not defined: they generate the value based on the content of the class file, hence coming up with unreadable meaningless long integers. If you want each and every version of your class to be distinct (in the eyes of the JVM) then you should not even specify the ...
How do I sort unicode strings alphabetically in Python?
...'t have word separators. You'll need to have a corpus of words to use as a base for the splitting, because that's not included, though.
It also has long names for the locales so you can get pretty display names for the locale, support for other calendars than Gregorian (although I'm not sure the Py...
How do I replace text inside a div element?
...e.js, not jQuery. In Prototype $ looks up an item by ID. It's not selector-based like jQuery is. api.prototypejs.org/dom/dollar
– ceejayoz
Oct 15 '12 at 2:11
...
What is cardinality in MySQL?
... @Pacerier: Yes, although I think that people working on databases are already quite familiar with relational theory, set theory and mathematics. And they borrowed the term from set theory: en.m.wikipedia.org/wiki/Cardinality
– Alexander Torstling
...