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HashSet versus Dictionary w.r.t searching time to find if an item exists
...P. I already have a dictionary i'm using for other reasons, and wanted to know if i benefit from changing to a Hashset instead of using ContainsKey. Looks like the answer is no since both are so fast.
– FistOfFury
Sep 12 '12 at 19:15
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C# Interfaces. Implicit implementation versus Explicit implementation
...Explicit is when you define methods within your class on the interface. I know that sounds confusing but here is what I mean: IList.CopyTo would be implicitly implemented as:
public void CopyTo(Array array, int index)
{
throw new NotImplementedException();
}
and explicitly as:
void ICollecti...
Sort rows in data.table in decreasing order on string key `order(-x,v)` gives error on data.table 1.
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Update
data.table v1.9.6+ now supports OP's original attempt and the following answer is no longer necessary.
You can use DT[order(-rank(x), y)].
x y v
1: c 1 7
2: c 3 8
3: c 6 9
4: b 1 1
5: b 3 2
6: b 6 3
7: a 1 4
8: a 3 5
9: a 6 6
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Assert a function/method was not called using Mock
...led attribute, but if your assertion fails, the next thing you'll want to know is something about the unexpected call, so you may as well arrange for that information to be displayed from the start. Using unittest, you can check the contents of call_args_list instead:
self.assertItemsEqual(my_var.c...
Adaptive segue in storyboard Xcode 6. Is push deprecated?
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Did that just now and at least for me "show" operated just like "push".
– Spencer Hall
Jun 25 '14 at 17:16
9
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Split (explode) pandas dataframe string entry to separate rows
...1 var2 var3
0 [a, b, c] 1 XX
1 [d, e, f, x, y] 2 ZZ
Now we can do this:
In [181]: pd.DataFrame({
...: col:np.repeat(x[col].values, x[lst_col].str.len())
...: for col in x.columns.difference([lst_col])
...: }).assign(**{lst_col:np.concatenate(x[lst_col]....
CSS Selector for
...
Ok I had tried this but it didn't work now it is working so I must have my syntax messed up.
– JoshBerke
Jan 22 '09 at 21:07
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Get pandas.read_csv to read empty values as empty string instead of nan
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Documentation for read_csv now offers both na_values (list or dict indexed by columns) and keep_default_na (bool). The keep_default_na value indicates whether pandas' default NA values should be replaced or appended to. The OP's code doesn't work curre...
How to set time zone of a java.util.Date?
...Instant objects for much of your business logic.
Instant instant = Instant.now();
OffsetDateTime
Apply an offset-from-UTC to adjust into some locality’s wall-clock time.
Apply a ZoneOffset to get an OffsetDateTime.
ZoneOffset zoneOffset = ZoneOffset.of( "-04:00" );
OffsetDateTime odt = OffsetDate...
What's the optimum way of storing an NSDate in NSUserDefaults?
... For the record - 32 bit floats have only 24 bits for accuracy, so 1970 to now is 40 years, which is 40*365*86400 seconds, and (40 * 365 * 86 400) / (2 ** 24) = 75second error. Double precision is what a DateTime interval, and its RAW precision is now better than a millionth of a second.
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