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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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How to write an async method with out parameter?
...to iterator methods -- i.e.
through the compiler transforming the method into a
state-machine-object. The CLR has no safe way to store the address of
an "out parameter" or "reference parameter" as a field of an object.
The only way to have supported out-by-reference parameters would be if
...
Android TextView with Clickable Links: how to capture clicks?
...nks. I need to capture clicks on the links and open the links -- in my own internal WebView (not in the default browser.)
1...
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 ...
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...
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&...
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...
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...
Drop data frame columns by name
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the subset function works better as it won't convert a data frame with one column into a vector
– mut1na
Jun 28 '13 at 9:06
3
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