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What is more efficient: Dictionary TryGetValue or ContainsKey+Item?
...
you can actually look at the .net source for it now too: referencesource.microsoft.com/#mscorlib/system/collections/… you can see that all 3 of TryGetValue, ContainsKey, and this[] call the same FindEntry method and do the same amount of work, only differing in how they...
How to Calculate Execution Time of a Code Snippet in C++
...t;
static timestamp_t
get_timestamp ()
{
struct timeval now;
gettimeofday (&now, NULL);
return now.tv_usec + (timestamp_t)now.tv_sec * 1000000;
}
...
timestamp_t t0 = get_timestamp();
// Process
timestamp_t t1 = get_timestamp();
double se...
Chrome: timeouts/interval suspended in background tabs?
I was testing the accuracy of setTimeout using this test . Now I noticed that (as expected) setTimeout is not very accurate but for most appliances not dramatically inaccurate. Now if I run the test in in Chrome and let it run in a background tab (so, switching to another tab and browse on ther...
How to get duration, as int milli's and float seconds from ?
...;
typedef std::chrono::duration<float> fsec;
auto t0 = Time::now();
auto t1 = Time::now();
fsec fs = t1 - t0;
ms d = std::chrono::duration_cast<ms>(fs);
std::cout << fs.count() << "s\n";
std::cout << d.count() << "ms\n";
}
which for m...
Run a callback only if an attribute has changed in Rails
...saving to the database, or within the before_save filter:
changes should now be changes_to_save
changed? should now be has_changes_to_save?
changed should now be changed_attribute_names_to_save
<attribute>_change should now be <attribute>_change_to_be_saved
<attribute>_changed? s...
Trouble comparing time with RSpec
...sides of your expectation
expect(@article.updated_at.utc.to_s).to eq(Time.now.to_s)
or
expect(@article.updated_at.utc.to_i).to eq(Time.now.to_i)
Refer to this for more information about why the times are different
shar...
How do you install Google frameworks (Play, Accounts, etc.) on a Genymotion virtual device? [duplica
... method is no longer supported by me and doesn't work anymore as far as I know. Don't try it.
# How To Add Google Apps and ARM Support to Genymotion v2.0+ #
Original Source: [GUIDE] Genymotion | Installing ARM Translation and GApps - XDA-Developers
Note(Feb 2nd): Contrary to previous reports, it's...
MySQL Query - Records between Today and Last 30 Days
...ery will not select the today's records.
In this case, you'll need to use NOW instead:
SELECT DATE_FORMAT(create_date, '%m/%d/%Y')
FROM mytable
WHERE create_date BETWEEN NOW() - INTERVAL 30 DAY AND NOW()
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How can I find the length of a number?
...ake its absolute value and adjust the sign afterwards.
Update for ES2015
Now that Math.log10 is a thing, you can simply write
const len = Math.ceil(Math.log10(num + 1));
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How can I make a time delay in Python? [duplicate]
I would like to know how to put a time delay in a Python script.
13 Answers
13
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