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Painless way to install a new version of R?
Andrew Gelman recently lamented the lack of an easy upgrade process for R (probably more relevant on Windows than Linux). Does anyone have a good trick for doing the upgrade, from installing the software to copying all the settings/packages over?
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how to find host name from IP with out login to the host
...s. When this option is used, there is no
need to provide the name, class and type arguments. dig automatically
performs a lookup for a name like 11.12.13.10.in-addr.arpa and sets
the query type and class to PTR and IN respectively.
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Case-insensitive search
...atched');
}
Using a regular expression like that is probably the tidiest and most obvious way to do that in JavaScript, but bear in mind it is a regular expression, and thus can contain regex metacharacters. If you want to take the string from elsewhere (eg, user input), or if you want to avoid ha...
Compare given date with today
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That format is perfectly appropriate for a standard string comparison e.g.
if ($date1 > $date2){
//Action
}
To get today's date in that format, simply use: date("Y-m-d H:i:s").
So:
$today = date("Y-m-d H:i:s");
$date = "2010-01-21 00:00:00";
if ($date < $t...
Switching between tabs in NERDTree
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An additional option (and my personal choice)beyond the ones listed by Michael Madsen:
gt = next tab
gT = previous tab
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Wrapping null-returning method in Java with Option in Scala?
...ause Try is not about nullability checking but just a way to functionally handle exceptions.
Using Try to catch an exception and converting that to an Option for convenience will only show None in case an exception happens.
scala> Try(1/0).toOption
res11: Option[Int] = None
You want to preser...
What is the difference between t.belongs_to and t.references in rails?
What is the difference between t.references and t.belongs_to ?
Why are we having those two different words? It seems to me they do the same thing?
Tried some Google search, but find no explanation.
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Counting the occurrences / frequency of array elements
In Javascript, I'm trying to take an initial array of number values and count the elements inside it. Ideally, the result would be two new arrays, the first specifying each unique element, and the second containing the number of times each element occurs. However, I'm open to suggestions on the form...
How do I put my website's logo to be the icon image in browser tabs?
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That image is called 'favicon' and it's a small square shaped .ico file, which is the standard file type for favicons. You could use .png or .gif too, but you should follow the standard for better compatibility.
To set one for your website you should:
M...
What does JVM flag CMSClassUnloadingEnabled actually do?
...//blogs.oracle.com/poonam/about-g1-garbage-collector,-permanent-generation-and-metaspace Kudos go to mt.uulu
For Java 5-7:
The standard Oracle/Sun VM look on the world is: Classes are forever. So once loaded, they stay in memory even if no one cares anymore. This usually is no problem since you do...