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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 to create Java gradle project
...ted to the gradle project. Then, how can I set the source folders automatically?
– verystrongjoe
May 15 '15 at 0:26
On...
What is WEB-INF used for in a Java EE web application?
... within the application hierarchy named
WEB-INF. This directory contains all things related to the
application that aren’t in the document root of the application. The
WEB-INF node is not part of the public document tree of the
application. No file contained in the WEB-INF directory may be...
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...
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...
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
...
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 ...