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Difference in make_shared and normal shared_ptr in C++
... difference is that std::make_shared performs one heap-allocation, whereas calling the std::shared_ptr constructor performs two.
Where do the heap-allocations happen?
std::shared_ptr manages two entities:
the control block (stores meta data such as ref-counts, type-erased deleter, etc)
the objec...
Test if a string contains any of the strings from an array
...omparison strings. A primitive way to make it case insensitive would be to call toLowerCase() or toUpperCase() on both the input and test strings.
If you need to do anything more complicated than this, I would recommend looking at the Pattern and Matcher classes and learning how to do some regular e...
How to concatenate columns in a Postgres SELECT?
...d string literal ', ' defaults to type text making the whole expression valid in any case.
For non-string data types, you can "fix" the 1st statement by casting at least one argument to text. (Any type can be cast to text):
SELECT a::text || b AS ab FROM foo;
Judging from your own answer, "does ...
Dynamically update values of a chartjs chart
... .update(config)
Triggers an update of the chart. This can be safely called after updating the data object. This will update all scales, legends, and then re-render the chart. A config object can be provided with additional configuration for the update process.
update() can be safely called...
Linear Regression and group by in R
...)
fits <- lmList(response ~ year | state, data=d)
fits
#------------
Call: lmList(formula = response ~ year | state, data = d)
Coefficients:
(Intercept) year
CA -1.34420990 0.17139963
NY 0.00196176 -0.01852429
Degrees of freedom: 20 total; 16 residual
Residual standard error: 0.82...
How do you serve a file for download with AngularJS or Javascript?
...?|ftp|mailto|tel|file|blob):/);
}]);
Please note that
Each time you call createObjectURL(), a new object URL is created, even if you've already created one for the same object. Each of these must be released by calling URL.revokeObjectURL() when you no longer need them. Browsers will release ...
How do I get the current date and time in PHP?
... using date_default_timezone_set before the date() or time() functions are called to.
I'm in Melbourne, Australia so I have something like this:
date_default_timezone_set('Australia/Melbourne');
Or another example is LA - US:
date_default_timezone_set('America/Los_Angeles');
You can also see ...
C# if/then directives for debug vs release
...nly executed if a certain symbol is defined. The compiler would remove all calls to those methods if the symbol is not defined:
[Conditional("DEBUG")]
void PrintLog() {
Console.WriteLine("Debug info");
}
void Test() {
PrintLog();
}
...
List comprehension vs map
...
map may be microscopically faster in some cases (when you're NOT making a lambda for the purpose, but using the same function in map and a listcomp). List comprehensions may be faster in other cases and most (not all) pythonistas consider them mo...
Android: Clear Activity Stack
...n navigates to login Screen and from there user can exit by cancel button (calling system.exit(0) )
11 Answers
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