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filter for complete cases in data.frame using dplyr (case-wise deletion)
...data.frame for complete cases using dplyr? complete.cases with a list of all variables works, of course. But that is a) verbose when there are a lot of variables and b) impossible when the variable names are not known (e.g. in a function that processes any data.frame).
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How to return 2 values from a Java method?
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You can use SimpleEntry<type_of_value_1, type_of_value_2> from java.util.AbstractMap.SimpleEntry and use it with getKey() to get object 1 and getValue() to get object 2
– Crystalonics
Apr 28 '16 at 18:03
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How to copy a directory using Ant
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@s1n This commands only copies all the contents of src_dir to ../new/dir and not the src_dir. How do we copy src_dir (directory) to another location?
– Pipalayan Nayak
Dec 3 '11 at 19:24
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MFC RadioButton用法详解 - C/C++ - 清泛网 - 专注C/C++及内核技术
...件定义Control变量或Value变量，每组只能定义一个）
BOOL m_Radio1;//对应于组 1 1
BOOL m_Radio3; //对应于组 2 1
BOOL m_Radio7; //对应于组 3 1
BOOL m_Radio9; //对应于组 4 1
CButton m_RBtGroup1; //对应于组 1 1
CButton m_RBtGroup2;...
Correct way to define Python source code encoding
...f you want to be 100% python-docs-recommendation-compatible.
More specifically, you need to use whatever is recognized by Python and the specific editing software you use (if it needs/accepts anything at all). E.g. the coding form is recognized (out of the box) by GNU Emacs but not Vim (yes, withou...
Getting an “ambiguous redirect” error
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Bash can be pretty obtuse sometimes.
The following commands all return different error messages for basically the same error:
$ echo hello >
bash: syntax error near unexpected token `newline`
$ echo hello > ${NONEXISTENT}
bash: ${NONEXISTENT}: ambiguous redirect
$ echo hello ...
Storing sex (gender) in database
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I'd call the column "gender".
Data Type Bytes Taken Number/Range of Values
------------------------------------------------
TinyINT 1 255 (zero to 255)
INT 4 - 2,147,483,...
How to implement has_many :through relationships with Mongoid and mongodb?
...uire multiple queries.
https://github.com/mongoid/mongoid/issues/544
Normally if you have a many-many relationship in a RDBMS you would model that differently in MongoDB using a field containing an array of 'foreign' keys on either side. For example:
class Physician
include Mongoid::Document
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Set title background color
...stomTitleBar" android:theme="@style/customTheme" ...
From the Activity (called CustomTitleBar) :
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_CUSTOM_TITLE);
setContentView(R.layout.main);
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What is an OS kernel ? How does it differ from an operating system? [closed]
...ernel is an operating system in that sense.
The end-user definition is usually something around "a software package that provides a desktop, shortcuts to applications, a web browser and a media player". A kernel doesn't match that definition.
So for an end-user a Linux distribution (say Ubuntu) is...