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Performance of Find() vs. FirstOrDefault() [duplicate]
...ject an anonmyous data item just for compilation
List<\u003C\u003Ef__AnonymousType0<string>> source = Enumerable.ToList(Enumerable.Select(Enumerable.Range(0, 1000000), i =>
{
var local_0 = new
{
Name = Guid.NewGuid().ToString()
};
return local_...
How to get last items of a list in Python?
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a negative index will count from the end of the list, so:
num_list[-9:]
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How can I use if/else in a dictionary comprehension?
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@Marcin's answer covers it all, but just in case someone wants to see an actual example, I add two below:
Let's say you have the following dictionary of sets
d = {'key1': {'a', 'b', 'c'}, 'key2': {'foo', 'bar'}, 'key3': {'so', 'sad'}}
and you want ...
Accessing nested JavaScript objects and arays by string path
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great stuff; using the lodash library, one can also do: _.get(object, nestedPropertyString);
– ian
Aug 13 '15 at 12:49
17
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SyntaxError: Non-ASCII character '\xa3' in file when function returns '£'
... First line is to make the py file executable on *nix. It is not really related to this question.
– cmd
Dec 15 '17 at 20:21
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Why is __dirname not defined in node REPL?
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Yeah, that should really be added to the answer Eye, because that's what got me.
– Tomáš Zato - Reinstate Monica
Oct 12 '15 at 17:14
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How to select rows from a DataFrame based on column values?
...have multiple values you want to include, put them in a
list (or more generally, any iterable) and use isin:
print(df.loc[df['B'].isin(['one','three'])])
yields
A B C D
0 foo one 0 0
1 bar one 1 2
3 bar three 3 6
6 foo one 6 12
7 foo three 7 14
Note,...
Guaranteed lifetime of temporary in C++?
...or the lifetime of a temporary variable that is created within a function call but not used as a parameter? Here's an example class:
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Variable number of arguments in C++?
...u can probably do what you want to do in a safer and simpler way. Technically to use variable number of arguments in C you include stdarg.h. From that you'll get the va_list type as well as three functions that operate on it called va_start(), va_arg() and va_end().
#include<stdarg.h>
int...
How do I clear only a few specific objects from the workspace?
I would like to remove some data from the workspace. I know the "Clear All" button will remove all data. However, I would like to remove just certain data.
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