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Passing references to pointers in C++
...; val)
{
//val is valid even after function call
val = new std::string("Test");
}
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Swift - How to convert String to Double
...ng, and returns nil when the string does not contain a Double value (e.g. "test" will not return 0.0).
let double = NSNumberFormatter().numberFromString(myString)?.doubleValue
Alternatively, extending Swift's String type:
extension String {
func toDouble() -> Double? {
return Numb...
How do you overcome the HTML form nesting limitation?
...tatement, you will be able to view the support for this feature here: html5test.com/compare/feature/form-association-form.html. IE is a write-off, most other desktop browsers seem tolerable.
– fatty
Dec 22 '13 at 3:57
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Difference between __getattr__ vs __getattribute__
... the attribute wasn't found the usual ways. It's good for implementing a fallback for missing attributes, and is probably the one of two you want.
__getattribute__ is invoked before looking at the actual attributes on the object, and so can be tricky to implement correctly. You can end up in infi...
What is Data Transfer Object?
...ot contain any business logic or methods implementation that would require testing.
Normally your model (using the MVC pattern) are intelligent models, and they can contain a lot of/some methods that do some different operations for that model specifically (not business logic, this should be at the...
How can I get `find` to ignore .svn directories?
...
@Kaleb: As comparing the file type (equivalent to testing whether a bit is set in an integer) is faster than comparing the filename (equivalent to a string comparison, which is O(n)), putting -type d before -name .svn is theoretically more efficient. However, it is usually i...
How do you clear the SQL Server transaction log?
... of the fact every time I need to do something beyond the basics. I have a test database that is not large in size, but the transaction log definitely is. How do I clear out the transaction log?
...
How to implement classic sorting algorithms in modern C++?
...erators.
Details omitted:
selection sort can be optimized with an early test if (std::distance(first, last) <= 1) return; (or for forward / bidirectional iterators: if (first == last || std::next(first) == last) return;).
for bidirectional iterators, the above test can be combined with a loop ...
Remove rows with duplicate indices (Pandas DataFrame and TimeSeries)
...-1]
df = df.iloc[ np.unique( df.index.values, return_index = True )[1] ]
Tests: 10k loops using OP's data
numpy method - 3.03 seconds
df.loc[~df.index.duplicated(keep='first')] - 4.43 seconds
df.groupby(df.index).first() - 21 seconds
reset_index() method - 29 seconds
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set date in input type date
...
Tested in Chrome and Edge & found working fine. As @Skipjack said, is awesome Answer !
– Arun
Feb 20 at 5:08
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