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Why does += behave unexpectedly on lists?
... immutable types, which might seem a strange design decision until you consider that otherwise you couldn't use += on immutable types like numbers!
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Aggregate / summarize multiple variables per group (e.g. sum, mean)
...reshape2 package for this task:
require(reshape2)
df_melt <- melt(df1, id = c("date", "year", "month"))
dcast(df_melt, year + month ~ variable, sum)
# year month x1 x2
1 2000 1 -80.83405 -224.9540159
2 2000 2 -223.76331 -288.2418017
3 2000 3 -188.83930 -481.560...
Automatically update version number
...uary 1st, 2000, and sets the revision part to the number of seconds since midnight, local time, divided by two. See this MSDN article.
Assembly version is located in an assemblyinfo.vb or assemblyinfo.cs file. From the file:
' Version information for an assembly consists of the following four val...
ant warning: “'includeantruntime' was not set”
...;
If you have to use the javac-task multiple times you might want to consider using PreSetDef to define your own javac-task that always sets includeantruntime="false".
Additional Details
From http://www.coderanch.com/t/503097/tools/warning-includeantruntime-was-not-set:
That's caused by a mi...
Using Custom Domains With IIS Express
...lect IIS Express ▼ from the drop down
Project Url: http://localhost
Override application root URL: http://dev.example.com
Click Create Virtual Directory (if you get an error here you may need to disable IIS 5/6/7/8, change IIS's Default Site to anything but port :80, make sure Skype isn't using po...
What are the implications of using “!important” in CSS? [duplicate]
...portant:
Specificity is one of the main forces at work when the browser decides how CSS affects the page. The more specific a selector is, the more importance is added to it. This usually coincides with how often the selected element occurs. For example:
button {
color: black;
}
button.highl...
Large, persistent DataFrame in pandas
...at all of them together into one DataFrame. Does the DataFrame have to reside in memory? With SAS, I can work with datasets of any size as long as I have the hard-drive space. Is it the same with DataFrames? I get the impression they are constrained by RAM and not hard-drive space. Sorry for th...
Java Mouse Event Right Click
On my three button mouse MouseEvent.BUTTON2 = Middle Click and MouseEvent.BUTTON3 = Right Click.
3 Answers
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Unable to understand useCapture parameter in addEventListener
..., DOM3 events: "the implementation must determine the current target's candidate event listeners. This must be the list of all event listeners that have been registered on the current target in their order of registration."
– Rob W
Sep 12 '14 at 20:47
...
Is it possible to use the SELECT INTO clause with UNION [ALL]?
...When we select all records it gives error as- "The ORDER BY clause is invalid in views, inline functions, derived tables, subqueries, and common table expressions, unless TOP or FOR XML is also specified. ". Please give some solution.
– ShaileshDev
Mar 21 '17 a...