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Subtract days from a date in JavaScript
...ime. So will correctly subtract 7 days time from the Date object. When you convert it to a string in your specified time zone it will correctly show the time for that zone.
– awjr
Oct 2 '15 at 14:40
...
How to check if a word is an English word with Python?
...
The same mention applies here too: a lot faster when converted to a set: set(words.words())
– Iulius Curt
Sep 30 '14 at 19:41
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Fastest way to reset every value of std::vector to 0
What's the fastest way to reset every value of a std::vector<int> to 0 and keeping the vectors initial size ?
6 An...
What is the difference between 'typedef' and 'using' in C++11?
...ef]/2 [extract, emphasis mine]
[dcl.typedef]/2 A
typedef-name
can also be introduced by an
alias-declaration.
The identifier following the using keyword becomes a
typedef-name and the optional attribute-specifier-seq following the identifier appertains to that typedef-name. Such a
typedef-name has ...
Why would anyone use set instead of unordered_set?
C++0x is introducing unordered_set which is available in boost and many other places. What I understand is that unordered_set is hash table with O(1) lookup complexity. On the other hand, set is nothing but a tree with log(n) lookup complexity. Why on earth would anyone use set instead ...
Create batches in linq
...ite any code. Use MoreLINQ Batch method, which batches the source sequence into sized buckets (MoreLINQ is available as a NuGet package you can install):
int size = 10;
var batches = sequence.Batch(size);
Which is implemented as:
public static IEnumerable<IEnumerable<TSource>> Batch&...
Extracting just Month and Year separately from Pandas Datetime column
...ore. Using df.my_date_column.astype('datetime64[M]'), as in @Juan's answer converts to dates representing the first day of each month.
– Nickolay
May 26 '18 at 19:52
4
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make_unique and perfect forwarding
...ith its use, in which case no function is exception safe. Consider void f( int *, int* ){}, clearly offers the no throw guarantee, but by your line of reasoning it is not exception safe, as it can be misused. Worse, void f( int, int ) {} is not exception safe either!: typedef unique_ptr<int> u...
Adding a new SQL column with a default value
...
Try this:
ALTER TABLE table1 ADD COLUMN foo INT DEFAULT 0;
From the documentation that you linked to:
ALTER [ONLINE | OFFLINE] [IGNORE] TABLE tbl_name
alter_specification [, alter_specification] ...
alter_specification:
...
ADD [COLUMN] (col_name colum...
Numpy - add row to array
...e necessary after every row, it's much quicker to add rows in python, then convert to numpy. Here are timing tests using python 3.6 vs. numpy 1.14, adding 100 rows, one at a time:
import numpy as np
from time import perf_counter, sleep
def time_it():
# Compare performance of two methods for a...