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jQuery Set Select Index
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+1 - The second option worked for me. The chosen answer by John Kugelman did not work for me in IE7.
– P.Brian.Mackey
Jun 27 '11 at 17:44
2
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Rotating a point about another point (2D)
... operation (i.e. calculating the inverse angle and then rotating clockwise by that amount)? I've seen a ton of pages giving this same formula, but nobody ever seems to see fit to talk about directionality in relation to the input / output values...
– NetXpert
A...
Filter data.frame rows by a logical condition
...le NAs and drop them from the resulting dataframe.
Running this on a 9840 by 24 dataframe 50000 times, it seems like the which method has a 60% faster run time than the %in% method.
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improv...
ggplot2 legend to bottom and horizontal
... 'theme' instead. (Deprecated; last used in version 0.9.1). Replacing opts by theme works.
– krlmlr
Apr 10 '13 at 22:33
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How do I navigate in the results of Diff
...it should show you the command shortcuts for doing page up/page down etc.
By default git looks at the $GIT_PAGER, then $PAGER environment variable to determine the program to be used for showing you the output of diff, log, show etc.
On new (linux) systems the default $PAGER used (even when it is ...
What does the 'Z' mean in Unix timestamp '120314170138Z'?
...iki/Coordinated_Universal_Time:
The UTC time zone is sometimes denoted by the letter Z—a reference to
the equivalent nautical time zone (GMT), which has been denoted by a Z
since about 1950. The letter also refers to the "zone description" of
zero hours, which has been used since 1920 (s...
Virtualbox “port forward” from Guest to Host [closed]
...//127.0.0.1:8000
or your network ip address (find out on the host machine by running: ipconfig).
Network communication Guest -> Host
In this case port forwarding is not needed, the communication goes over the LAN back to the host.
On the host machine - find out your netw ip address:
ipconfig
ex...
tomcat - CATALINA_BASE and CATALINA_HOME variables
...tallation.
Optionally, Tomcat may be configured for multiple instances by defining $CATALINA_BASE for each instance. If multiple instances are not configured, $CATALINA_BASE is the same as $CATALINA_HOME.
See: Apache Tomcat 7 - Introduction
Running with separate CATALINA_HOME and CATALINA_BAS...
POST JSON fails with 415 Unsupported media type, Spring 3 mvc
...son',
'success': callback
});
};
The Content-Type header is used by @RequestBody to determine what format the data being sent from the client in the request is. The accept header is used by @ResponseBody to determine what format to sent the data back to the client in the response. That's w...
Repeat each row of data.frame the number of times specified in a column
... 1:2]
The code for data.table is a tad cleaner:
# convert to data.table by reference
setDT(df)
df.expanded <- df[rep(seq(.N), freq), !"freq"]
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