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Find the day of a week
...a.frame(date=c("2012-02-01", "2012-02-01", "2012-02-02"))
df$day <- weekdays(as.Date(df$date))
df
## date day
## 1 2012-02-01 Wednesday
## 2 2012-02-01 Wednesday
## 3 2012-02-02 Thursday
Edit: Just to show another way...
The wday component of a POSIXlt object is the numeric wee...
What is a mutex?
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When I am having a big heated discussion at work, I use a rubber chicken which I keep in my desk for just such occasions. The person holding the chicken is the only person who is allowed to talk. If you don't hold the chicken you cannot speak. You can only indicate tha...
Access Enum value using EL with JSTL
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A simple comparison against string works:
<c:when test="${someModel.status == 'OLD'}">
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Parse query string into an array
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Giacomo1968
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answered Mar 22 '11 at 21:01
AnthonyAnthony
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How to get an object's properties in JavaScript / jQuery?
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You can look up an object's keys and values by either invoking JavaScript's native for in loop:
var obj = {
foo: 'bar',
base: 'ball'
};
for(var key in obj) {
alert('key: ' + key + '\n' + 'value: ' + obj[key]);
}
or ...
move_uploaded_file gives “failed to open stream: Permission denied” error
I keep getting this error when trying to configure the upload directory with Apache 2.2 and PHP 5.3 on CentOS.
13 Answers
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How to resize the jQuery DatePicker control
I'm using the jQuery DatePicker control for the first time. I've got it working on my form, but it's about twice as big as I would like, and about 1.5 times as big as the demo on the jQuery UI page. Is there some simple setting I'm missing to control the size?
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How to SSH to a VirtualBox guest externally through a host? [closed]
...should have one interface already which is using NAT. Then go to the Network settings and click the Port Forwarding button. Add a new Rule. As the rule name, insert "ssh". As "Host port", insert 3022. As "Guest port", insert 22. Everything else of the rule can be left blank.
or from the command li...
Quick and easy file dialog in Python?
...riendly, especially because the user can't copy/paste the path. I would like a quick and easy way to present a file selection dialog to the user, they can select the file, and then it's loaded to the database. (In my use case, if they happened to chose the wrong file, it would fail parsing, and wo...
Reopen last closed tab in Visual Studio
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StormenetStormenet
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