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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...
XPath: How to select nodes which have no attributes?
...
//node[not(@*)]
That's the XPath to select all nodes named "node" in the document without any attributes.
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Maven parent pom vs modules pom
...ructure (pattern #2):
root/
parent-pom/
pom.xml
projectA/
Optionally, you can even add a pom.xml in the trunks directory:
root
|-- parent-pom
| |-- branches
| |-- tags
| `-- trunk
| `-- pom.xml
|-- projectA
| |-- branches
| |-- tags
| `-- trunk
| |-- module1
| ...
How to convert a Git shallow clone to a full clone?
Follow-up of this so-question: if I have a shallow clone, how to fetch all older commits to make it a full clone?
6 Answe...
How does this CSS produce a circle?
...
Let's reformulate that into two questions:
Where do width and height actually apply?
Let's have a look at the areas of a typical box (source):
The height and width apply only on content, if the correct box model is being used (no quirks mode, no old Internet Explorer).
Where does border-radi...
How to change the author and committer name and e-mail of multiple commits in Git?
...ch the docs now give this warning:
git filter-branch has a plethora of pitfalls that can produce non-obvious manglings of the intended history rewrite (and can leave you with little time to investigate such problems since it has such abysmal performance). These safety and performance issues cannot b...
Visual Studio Expand/Collapse keyboard shortcuts [duplicate]
...code file open, I can press CTRL + M or CTRL + M + O to collapse all code blocks, regions, namespaces, etc.
7 Ans...
Difference between .on('click') vs .click()
....on over .click because the former can use less memory and work for dynamically added elements.
Consider the following html:
<html>
<button id="add">Add new</button>
<div id="container">
<button class="alert">alert!</button>
</div>
<...
Why can't strings be mutable in Java and .NET?
...ctly one state, the state in which it was created. If you make sure
that all constructors establish class invariants, then it is
guaranteed that these invariants will remain true for all time, with
no effort on your part.
[...]
Immutable objects are inherently thread-safe; they requi...
How to hide reference counts in VS2013?
...n my professional preview. But looking online I found that the feature is called Code Information Indicators or CodeLens, and can be located under
Tools → Options → Text Editor → All Languages → CodeLens
(for RC/final version)
or
Tools → Options → Text Editor → All L...