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Why were pandas merges in python faster than data.table merges in R in 2012?
...en of the comparison to data.table as presented.
UPDATE from data.table v1.8.0 released July 2012
Internal function sortedmatch() removed and replaced with chmatch()
when matching i levels to x levels for columns of type 'factor'. This
preliminary step was causing a (known) signif...
npm install from Git in a specific version
...sion with git tag -a "1.0.0" and pushed git push --tags, then I added the #v1.0.0 at the end of the git+ssh dependency. But at npm update nothing happens.
– loretoparisi
Apr 19 '16 at 8:31
...
Checking if an instance's class implements an interface?
...h:
Given an instance of an object
Object construction outside the loop (100,000 iterations)
____________________________________________
| class_implements | Reflection | instanceOf |
|------------------|------------|------------|
| 140 ms | 290 ms | 35 ms |
'-----------------...
How to reverse apply a stash?
...
The V1 git man page had a reference about un-applying a stash. The excerpt is below.
The newer V2 git man page doesn't include any reference to un-applying a stash but the below still works well
Un-applying a Stash
In some use ...
Save bitmap to location
... FileOutputStream(filename)) {
bmp.compress(Bitmap.CompressFormat.PNG, 100, out); // bmp is your Bitmap instance
// PNG is a lossless format, the compression factor (100) is ignored
} catch (IOException e) {
e.printStackTrace();
}
...
Test if string is a number in Ruby on Rails
...g -------------------------------------
# cast 57485 i/100ms
# cast fail 5549 i/100ms
# to_s 47509 i/100ms
# to_s fail 50573 i/100ms
# regexp 45187 i/100ms
# regexp fail 42566 i/100ms
# ------------...
裁员！裁员！创业者们的2016“寒冬大逃杀” - 资讯 - 清泛网 - 专注IT技能提升
...2、7、1”的末位淘汰制里，他长时间停留在最末“1”的位置。仅有完美的执行力是不够的，在创业公司的初期，速度和公司的存亡直接挂钩，没有足够的学习时间让他学习，成长为懂供应链、地推、物流的区域经理。
谈话进行...
How to Calculate Execution Time of a Code Snippet in C++
...N32
/* Windows */
FILETIME ft;
LARGE_INTEGER li;
/* Get the amount of 100 nano seconds intervals elapsed since January 1, 1601 (UTC) and copy it
* to a LARGE_INTEGER structure. */
GetSystemTimeAsFileTime(&ft);
li.LowPart = ft.dwLowDateTime;
li.HighPart = ft.dwHighDateTime;
uint64 ret...
How many GCC optimization levels are there?
...rpret the source code of GCC 5.1
We'll try to understand what happens on -O100, since it is not clear on the man page.
We shall conclude that:
anything above -O3 up to INT_MAX is the same as -O3, but that could easily change in the future, so don't rely on it.
GCC 5.1 runs undefined behavior if you...
How to customize user profile when using django-allauth
... what worked for me combining a few of the other answers (none of them are 100% complete and DRY).
In yourapp/forms.py:
from django.contrib.auth import get_user_model
from django import forms
class SignupForm(forms.ModelForm):
class Meta:
model = get_user_model()
fields = ['fi...