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Understanding slice notation
...t value that is not in the selected slice. So, the difference between stop and start is the number of elements selected (if step is 1, the default).
The other feature is that start or stop may be a negative number, which means it counts from the end of the array instead of the beginning. So:
a[-1]...
Is there Selected Tab Changed Event in the standard WPF Tab Control
...
I tied this in the handler to make it work:
void TabControl_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
if (e.Source is TabControl)
{
//do work when tab is changed
}
}
...
How to remove non-alphanumeric characters?
...be "~" or "@" or whatever character you want to use as long as the opening and closing delimiters are the same) and change the behavior of the expression.
– Doktor J
Apr 13 '14 at 22:04
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Execute code when Django starts ONCE only?
...ou want to execute code in the top-level urls.py. That module is imported and executed once.
urls.py
from django.confs.urls.defaults import *
from my_app import one_time_startup
urlpatterns = ...
one_time_startup()
sha...
How to make a countdown timer in Android?
...wo EditTexts in XML. In one EditText, the user can put a number as minutes and in another EditText, a number as seconds. After clicking the finish button, the seconds EditText should start to countdown and update its text every second.
...
How to convert a String to its equivalent LINQ Expression Tree?
...o you mean by "writing a parser (using Expression under the hood)" Parsing and then generating an expression tree, or does System.Linq.Expressions have some parsing mechanism?
– AK_
Jul 1 '13 at 14:51
...
Android: Difference between onInterceptTouchEvent and dispatchTouchEvent?
What is the difference between onInterceptTouchEvent and dispatchTouchEvent in Android?
14 Answers
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Does C# have extension properties?
...ot seen as valuable enough to be included in the previous versions of C# standard. C# 7 and C# 8.0 have seen this as proposal champion but it wasn't released yet, most of all because even if there is already an implementation, they want to make it right from the start.
But it will ...
There is an ...
Auto reloading python Flask app upon code changes
...
The current recommended way is with the flask command line utility.
https://flask.palletsprojects.com/en/1.1.x/quickstart/#debug-mode
Example:
$ export FLASK_APP=main.py
$ export FLASK_ENV=development
$ flask run
or in one command:
$ FLASK_APP=main.py FLASK_ENV=develo...
How are feature_importances in RandomForestClassifier determined?
......). It is sometimes called "gini importance" or "mean decrease impurity" and is defined as the total decrease in node impurity (weighted by the probability of reaching that node (which is approximated by the proportion of samples reaching that node)) averaged over all trees of the ensemble.
In th...