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Omit rows containing specific column of NA
...# 2 2 10 33
EDIT: Only return rows with no NAs
If you want to eliminate all rows with at least one NA in any column, just use the complete.cases function straight up:
DF[complete.cases(DF), ]
# x y z
# 2 2 10 33
Or if completeFun is already ingrained in your workflow ;)
completeFun(DF, na...
Are HTTP headers case-sensitive?
...case-sensitive.)
If you trust the major browsers to abide by this, you're all set.
BTW, unlike most of HTTP, methods (verbs) are case sensitive:
5.1.1 Method
The Method token indicates the
method to be performed on the
resource identified by the
Request-URI. The method is
case-sens...
Threads vs Processes in Linux
... threads -- everything is simply a runnable task. *
On Linux, the system call clone clones a task, with a configurable level of sharing, among which are:
CLONE_FILES: share the same file descriptor table (instead of creating a copy)
CLONE_PARENT: don't set up a parent-child relationship between t...
Git: Show all of the various changes to a single line in a specified file over the entire git histor
...
@Rob - thanks for this - small edit to your script though - putting just the filename only shows commits that just affect that file - if a commit referenced other files it is not listed
– Adrian Cornish
Sep 7 '12 ...
How do I select text nodes with jQuery?
I would like to get all descendant text nodes of an element, as a jQuery collection. What is the best way to do that?
11 An...
Why is “while ( !feof (file) )” always wrong?
...ol. The environment truly exists "concurrently" with your program. As with all things concurrent, questions about the "current state" don't make sense: There is no concept of "simultaneity" across concurrent events. Many properties of state simply don't exist concurrently.
Let me make this more prec...
For loop for HTMLCollection elements
I'm trying to set get id of all elements in an HTMLCollectionOf . I wrote the following code:
12 Answers
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Squash the first two commits in Git? [duplicate]
...
Update July 2012 (git 1.7.12+)
You now can rebase all commits up to root, and select the second commit Y to be squashed with the first X.
git rebase -i --root master
pick sha1 X
squash sha1 Y
pick sha1 Z
git rebase [-i] --root $tip
This command can now be used to ...
How do HttpOnly cookies work with AJAX requests?
...st to the server.
In the case of Stack Overflow, the cookies are automatically provided as part of the XmlHttpRequest request. I don't know the implementation details of the Stack Overflow authentication provider, but that cookie data is probably automatically used to verify your identity at a low...
What is an NP-complete in computer science?
...ng machine but also including a non-deterministic "choice" function). Basically, a solution has to be testable in poly time. If that's the case, and a known NP problem can be solved using the given problem with modified input (an NP problem can be reduced to the given problem) then the problem is NP...