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How can I explicitly free memory in Python?
...'m using python 3.6. Calling gc.collect() after loading a pandas dataframe from hdf5 (500k rows) reduced memory usage from 1.7GB to 500MB
– John
Jan 18 '18 at 20:30
...
Remove an item from a dictionary when its key is unknown
What is the best way to remove an item from a dictionary by value, i.e. when the item's key is unknown? Here's a simple approach:
...
How to get existing fragments when using FragmentPagerAdapter
...create Fragments for your ViewPager, but upon Activity recreation (whether from a device rotation or the system killing your App to regain memory) these Fragments won't be created again, but instead their instances retrieved from the FragmentManager. Now say your Activity needs to get a reference to...
Setting Environment Variables for Node to retrieve
...credentials to your application. USER_ID and USER_KEY can both be accessed from process.env.USER_ID and process.env.USER_KEY respectively. You don't need to edit them, just access their contents.
It looks like they are simply giving you the choice between loading your USER_ID and USER_KEY from eith...
What is the difference between the mouseover and mouseenter events?
...
You can try out the following example from the jQuery doc page. It's a nice little, interactive demo that makes it very clear and you can actually see for yourself.
var i = 0;
$("div.overout")
.mouseover(function() {
i += 1;
$(this).find("span"...
AngularJS ui-router login authentication
... // check and see if we have retrieved the
// identity data from the server. if we have,
// reuse it by immediately resolving
if (angular.isDefined(_identity)) {
deferred.resolve(_identity);
return deferred.promise;
}
// otherwise...
How can I delete one element from an array by value
... personally like [1, 2, 3, 4, 5] - [3] which results in => [1, 2, 4, 5] from irb.
– Travis
Apr 5 '12 at 19:31
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How do you rename a MongoDB database?
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How is this different from the solution provided by the OP?
– Salvador Dali
Apr 3 '14 at 3:26
6
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What is the purpose of the “final” keyword in C++11 for functions?
...rn already mentioned in a comment is that if you are overriding a function from a base class, then you cannot possibly mark it as non-virtual:
struct base {
virtual void f();
};
struct derived : base {
void f() final; // virtual as it overrides base::f
};
struct mostderived : derived {
...
How do I convert seconds to hours, minutes and seconds?
...ossible to use time.strftime, which gives more control over formatting:
from time import strftime
from time import gmtime
strftime("%H:%M:%S", gmtime(666))
'00:11:06'
strftime("%H:%M:%S", gmtime(60*60*24))
'00:00:00'
gmtime is used to convert seconds to special tuple format that strftime() re...