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Debug vs. Release performance
...ult. The ones
that move code around like
loop-invariant hoisting. In selected
cases, this can make a big difference
in performance. Not usually though.
Mapping breakpoints to execution
addresses is the job of the debugger.
It uses the .pdb file and info
generated by the JIT co...
How to save a plot as image on the disk?
...
How do I do this when R asks for a "Selection"? For example If I use m3=garchFit(~arma(3,0)+garch(1,1)) and plot(m3).
– jacob
Jan 25 '16 at 13:28
...
Inheriting constructors
... constructors, if you write this, you inherit all of them. To inherit only selected ones you need to write the individual constructors manually and call the base constructor as needed from them.
Historically constructors could not be inherited in the C++03 standard. You needed to inherit them manua...
Can't specify the 'async' modifier on the 'Main' method of a console app
...dvanced button at the bottom:
From the language version drop-down menu, select "7.1" (or any higher value):
The default is "latest major version" which would evaluate (at the time of this writing) to C# 7.0, which does not support async main in console apps.
...
Secret copy to clipboard JavaScript function in Chrome and Firefox?
... function(obj, panelName) // no web page interaction
{
Firebug.chrome.select(obj, panelName);
};
this.keys = function(o)
{
return FBL.keys(o); // the object is from the page, unwrapped
};
this.values = function(o)
{
return FBL.values(o); // the object is from the page, unwrapped
};
...
MySQL how to join tables on two fields
...
SELECT *
FROM t1
JOIN t2 USING (id, date)
perhaps you'll need to use INNEER JOIN or
where t2.id is not null
if you want results only matching both conditions
...
Is there a way to auto-adjust Excel column widths with pandas.ExcelWriter?
..._params)
#Output some SQL Server data into a dataframe
my_sql_query = """ SELECT * FROM dbo.my_table """
my_dataframe = pd.read_sql_query(my_sql_query,con=read_engine)
#Set destination directory to save excel.
xlsFilepath = r'H:\my_project' + "\\" + 'my_file_name.xlsx'
writer = pd.ExcelWriter(xlsF...
How can I time a code segment for testing performance with Pythons timeit?
...
Rather than select a clock by hand, use timeit.default_timer; Python has already done the work for you. But really, you should use timeit.timeit(myfast, number=n) instead of re-inventing the repetitive call wheel (and miss the fact that ...
What is sharding and why is it important?
... a DBMS for which the locality is quite restricted (say, a user only fires selects with a 'where username = $my_username') it makes sense to put all the usernames starting with A-M on one server and all from N-Z on the other. By this you get near linear scaling for some queries.
Long story short: S...
How to convert JSON to XML or XML to JSON?
...bject)d.Value);
if (xml.HasElements) attr.Add("_value", xml.Elements().Select(e => GetXmlData(e)));
else if (!xml.IsEmpty) attr.Add("_value", xml.Value);
return new Dictionary<string, object> { { xml.Name.LocalName, attr } };
}
...