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NSDate beginning of day and end of day
...o: noon)!
let specificDate = Date("2020-01-01")
extension Date {
init(_ dateString:String) {
let dateStringFormatter = DateFormatter()
dateStringFormatter.dateFormat = "yyyy-MM-dd"
dateStringFormatter.locale = NSLocale(localeIdentifier: "en_US_POSIX") as Locale
l...
How to take a screenshot programmatically on iOS
...iOS7 or above
- (UIImage *) screenshot {
CGSize size = CGSizeMake(your_width, your_height);
UIGraphicsBeginImageContextWithOptions(size, NO, [UIScreen mainScreen].scale);
CGRect rec = CGRectMake(0, 0, your_width, your_height);
[_viewController.view drawViewHierarchyInRect:rec afte...
How do I add indices to MySQL tables?
...
ALTER TABLE `table` ADD INDEX `product_id_index` (`product_id`)
Never compare integer to strings in MySQL. If id is int, remove the quotes.
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Rails 3 - can't install pg gem
When I try to run bundle (bundle install), I all the time get
16 Answers
16
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Limitations of SQL Server Express
...fering a fully managed dedicated server with SQL Server Web version () installed. My company handles web development, and has about 20+ clients using ASP.Net + SQL Server 2005.
...
How to change package name of an Android Application
...ould try these instructions from Android's developer site. They're specifically for the GestureBuilder sample but should apply to any application as far as I can tell:
[H]ere's how you could do this in Eclipse:
Right-click on the package name (src/com.android.gesture.builder).
Select R...
Relative frequencies / proportions with dplyr
...
Try this:
mtcars %>%
group_by(am, gear) %>%
summarise(n = n()) %>%
mutate(freq = n / sum(n))
# am gear n freq
# 1 0 3 15 0.7894737
# 2 0 4 4 0.2105263
# 3 1 4 8 0.6153846
# 4 1 5 5 0.3846154
From the dplyr vigne...
Should I pass a shared_ptr by reference? [duplicate]
...mber of bugs arise from improper lifetime management. What's worse conceptually is that it is never clear who owns the objects whose pointers the container stores. The pointers could even be a mix of pointers to dynamic objects, automatic objects, and garbage. Nobody can tell. So the standard soluti...
Difference between std::system_clock and std::steady_clock?
...11.7.1 [time.clock.system]/1:
Objects of class system_clock represent wall clock time from the system-wide realtime clock.
20.11.7.2 [time.clock.steady]/1:
Objects of class steady_clock represent clocks for which values of time_point never decrease as physical time advances and for which v...
Optional Parameters in Go?
...ety of
methods with the same name but
different signatures was occasionally
useful but that it could also be
confusing and fragile in practice.
Matching only by name and requiring
consistency in the types was a major
simplifying decision in Go's type
system.
...