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boost::flat_map and its performance compared to map and unordered_map
...erformance a lot due to cache hits. I recently found out about boost::flat_map which is a vector based implementation of a map. It doesn't seem to be nearly as popular as your typical map / unordered_map so I haven't been able to find any performance comparisons. How does it compare and what are...
Avoid duplicates in INSERT INTO SELECT query in SQL Server
...
Using NOT EXISTS:
INSERT INTO TABLE_2
(id, name)
SELECT t1.id,
t1.name
FROM TABLE_1 t1
WHERE NOT EXISTS(SELECT id
FROM TABLE_2 t2
WHERE t2.id = t1.id)
Using NOT IN:
INSERT INTO TABLE_2
(id, name)
SELECT t...
Git - How to use .netrc file on Windows to save user and password
...onment variable %HOME% (pre-Git 2.0, no longer needed with Git 2.0+)
put a _netrc file in %HOME%
If you are using Windows 7/10, in a CMD session, type:
setx HOME %USERPROFILE%
and the %HOME% will be set to 'C:\Users\"username"'.
Go that that folder (cd %HOME%) and make a file called '_netrc'
N...
How can I setup & run PhantomJS on Ubuntu?
...antomJS and recorded it to video: https://www.dailymotion.com/video/xnizmh_1_webcam
25 Answers
...
What is the purpose of the word 'self'?
...
But in __init__(self) method, it accepts self, then even without creating the object, how does it refer to itself?
– saurav
Jan 28 '18 at 10:10
...
Trying to mock datetime.date.today(), but not working
...ock.patch('datetime.date.today')
def test():
datetime.date.today.return_value = date(2010, 1, 1)
print datetime.date.today()
Unfortunately, this won't work:
>>> test()
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "build/bdist.macosx-...
JSON datetime between Python and JavaScript
...
You can add the 'default' parameter to json.dumps to handle this:
date_handler = lambda obj: (
obj.isoformat()
if isinstance(obj, (datetime.datetime, datetime.date))
else None
)
json.dumps(datetime.datetime.now(), default=date_handler)
'"2010-04-20T20:08:21.634121"'
Which is ISO 8...
Styling Google Maps InfoWindow
...unction InfoBox(opts) {
google.maps.OverlayView.call(this);
this.latlng_ = opts.latlng;
this.map_ = opts.map;
this.offsetVertical_ = -195;
this.offsetHorizontal_ = 0;
this.height_ = 165;
this.width_ = 266;
var me = this;
this.boundsChangedListener_ =
google.maps.event.addListe...
App Inventor 2 数据可视化教程 - 折线图/曲线图/实时数据绘图 · App Inventor 2 中文网
...线图）
积木块：
// 全局变量
global x计数 = 0
when 按钮_开始.Click() {
计时器1.TimerEnabled = true
二维图表数据1.Clear()
}
when 计时器1.Timer() {
global x计数 = x计数 + 1
global 随机值 = randomInteger(1, 100)
二维图表数据1.AddEntry(x计数, 随...
Allowed characters in Linux environment variable names
...EE Std
1003.1-2001 consist solely of uppercase letters, digits, and the '_'
(underscore) from the characters
defined in Portable Character Set and
do not begin with a digit. Other
characters may be permitted by an
implementation; applications shall
tolerate the presence of such names.
...