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Checking if a string can be converted to float in Python
... ------------
print(isfloat("")) False
print(isfloat("1234567")) True
print(isfloat("NaN")) True nan is also float
print(isfloat("NaNananana BATMAN")) False
print(isfloat("123.456")) True
print(isfloat("123.E4")) ...
How do I (or can I) SELECT DISTINCT on multiple columns?
...eUploader: {
brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 4...
Is there a way to get a collection of all the Models in your Rails app?
...ase. Don't know how you can list all the classes though...
EDIT: Just for fun, I found a way to list all classes
Module.constants.select { |c| (eval c).is_a? Class }
EDIT: Finally succeeded in listing all models without looking at directories
Module.constants.select do |constant_name|
constan...
How to search through all Git and Mercurial commits in the repository for a certain string?
...ways to do that. See "hg help revsets", esp the desc(), user(), and file() functions. There are also hg log switches for most of this behavior. In my experience, though -k/keyword() is usually the most helpful way to search for things.
– Kevin Horn
Dec 17 '12...
How can I make a horizontal ListView in Android? [duplicate]
...) There is no recycling of views. Maybe it would be possible to tack this functionality onto the scroll view, but it seems to me that it would mess with the scrolling behavior, and it would be nearly as much work as simply extending AdapterView.
– Neil Traft
O...
Play sound on button click android
...
mp = MediaPlayer.create(context, R.raw.sound_two);
and play it !
Have fun!
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What does the “yield” keyword do?
...one, etc. And generators return... well that's where yield comes in:
def f123():
yield 1
yield 2
yield 3
for item in f123():
print item
Instead of yield statements, if you had three return statements in f123() only the first would get executed, and the function would exit. But f1...
How to detect when an Android app goes to the background and come back to the foreground
...to a Google I/O talk:
class YourApplication : Application() {
override fun onCreate() {
super.onCreate()
registerActivityLifecycleCallbacks(AppLifecycleTracker())
}
}
class AppLifecycleTracker : Application.ActivityLifecycleCallbacks {
private var numStarted = 0
override fun ...
module.exports vs exports in Node.js
...:
var x = require('file1.js');
contents of file1.js:
module.exports = '123';
When the above statement is executed, a Module object is created. Its constructor function is:
function Module(id, parent) {
this.id = id;
this.exports = {};
this.parent = parent;
if (parent &&...
CSS \9 in width property
... \0 instead of \9 will apply it to IE10 as well
– abc123
Oct 9 '13 at 21:26
21
@abc123 lets hope ...