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Why were pandas merges in python faster than data.table merges in R in 2012?
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It looks like Wes may have discovered a known issue in data.table when the number of unique strings (levels) is large: 10,000.
Does Rprof() reveal most of the time spent in the call sortedmatch(levels(i[[lc]]), levels(x[[rc]])? This isn't really the join itself (t...
Parsing CSV files in C#, with header
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A CSV parser is now a part of .NET Framework.
Add a reference to Microsoft.VisualBasic.dll (works fine in C#, don't mind the name)
using (TextFieldParser parser = new TextFieldParser(@"c:\temp\test.csv"))
{
parser.TextFieldType = Field...
How do I show the value of a #define at compile-time?
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I know that this is a long time after the original query, but this may still be useful.
This can be done in GCC using the stringify operator "#", but it requires two stages.
#define XSTR(x) STR(x)
#define STR(x) #x
The value...
URLs: Dash vs. Underscore [closed]
...le Webmasters: youtube.com/watch?v=AQcSFsQyct8. Per that video (admittedly now 6 years old and possibly not representing the contemporary status quo), foo_bar is treated as a single word while foo-bar is treated as two words - precisely the opposite of what this answer speculates is the case.
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How do I grant myself admin access to a local SQL Server instance?
...the command prompt to stop the SQL Server service:
net stop mssqlserver
Now go to the directory where SQL server is installed. The directory can for instance be one of these:
C:\Program Files\Microsoft SQL Server\MSSQL10_50.MSSQLSERVER\MSSQL\Binn
C:\Program Files\Microsoft SQL Server\MSSQL13.MS...
How to find all positions of the maximum value in a list?
... leading coefficients are ignored in big O
– michaelsnowden
Oct 23 '15 at 8:06
1
Theoretically O(...
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock'
...lin) and then set root password on phpMyAdmin . I forgot the password and now I am unable to login. When I try to change password through terminal I get:
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How to increase font size in the Xcode editor?
...font will be preselected in the font inspector. Whatever changes you make now
will be applied to the text types you selected in the 'Source Editor' window.
e.g. All Fonts > Menlo > Regular > 14
Close the windows you opened on this hunt for the holy grail.
Congratulations. Your may now...
When to use self over $this?
...I did get some more information that I found helpful further down, but for now I was just trying to figure out why I hit my class attributes with $this->attrib and the class constants with self::constant. This helped me understand that better
– MydKnight
Jul...
Click Event on UIImageView programmatically in ios
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Now in Swift!
let singleTap = UITapGestureRecognizer(target: self, action: Selector("tapDetected"))
singleTap.numberOfTapsRequired = 1
preArrowImage.userInteractionEnabled = true
preArrowImage.addGestureRecognizer(singleTap...