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How do you delete a column by name in data.table?
...hod 3 (could then assign to df3,
df3[, !"foo"]
though if you were actually wanting to remove column "foo" from df3 (as opposed to just printing a view of df3 minus column "foo") you'd really want to use Method 1 instead.
(Do note that if you use a method relying on grep() or grepl(), you need ...
Is it possible to “decompile” a Windows .exe? Or at least view the Assembly?
...ious to see what it does without infecting myself. I know that you can't really decompile an .exe, but can I at least view it in Assembly or attach a debugger?
...
How to use 'find' to search for files created on a specific date? [closed]
...nted out by Max, you can't, but checking files modified or accessed is not all that hard. I wrote a tutorial about this, as late as today. The essence of which is to use -newerXY and ! -newerXY:
Example: To find all files modified on the 7th of June, 2007:
$ find . -type f -newermt 2007-06-07 ! -...
How long do browsers cache HTTP 301s?
...'s cache can accommodate it. It will be removed from the cache if you manually clear the cache, or if the cache entries are purged to make room for new ones.
You can verify this at least in Firefox by going to about:cache and finding it under disk cache. It works this way in other browsers includi...
ActiveRecord.find(array_of_ids), preserving order
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The answer is for mysql only
There is a function in mysql called FIELD()
Here is how you could use it in .find():
>> ids = [100, 1, 6]
=> [100, 1, 6]
>> WordDocument.find(ids).collect(&:id)
=> [1, 6, 100]
>> WordDocument.find(ids, :order => "field(id,...
How can I get a list of build targets in Ant?
... the available built targets without having to search through the file manually. Does ant have a command for this - something like ant show-targets - that will make it list all the targets in the build file?
...
How to generate a random integer number from within a range
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All the answers so far are mathematically wrong. Returning rand() % N does not uniformly give a number in the range [0, N) unless N divides the length of the interval into which rand() returns (i.e. is a power of 2). Furthe...
SVN best-practices - working in a team
...t be, "trunk must always build without errors." or "trunk must always pass all unit tests". Any work that can't yet meet the standards of trunk must be done in a branch.
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What is a bank conflict? (Doing Cuda/OpenCL programming)
...ank 2, ..., 64-69 in bank 1 and so on). For a better visualization it basically looks like this:
Bank | 1 | 2 | 3 |...
Address | 0 1 2 3 | 4 5 6 7 | 8 9 10 11 |...
Address | 64 65 66 67 | 68 69 70 71 | 72 73 74 75 |...
...
So if each thread in a halfwarp...
Google Chromecast sender error if Chromecast extension is not installed or using incognito
...hromecast sender in Chrome Incognito or if Chromecast extension is not installed:
5 Answers
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