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Remove rows with all or some NAs (missing values) in data.frame
...na.omit is nicer for just removing all NA's. complete.cases allows partial selection by including only certain columns of the dataframe:
> final[complete.cases(final[ , 5:6]),]
gene hsap mmul mmus rnor cfam
2 ENSG00000199674 0 2 2 2 2
4 ENSG00000207604 0 NA NA ...
String vs. StringBuilder
... .NET are immutable). It works by keeping an internal buffer, an array of char. Calling Append() or AppendLine() adds the string to the empty space at the end of the char array; if the array is too small, it creates a new, larger array, and copies the buffer there. So in the example above, String...
How can I output the value of an enum class in C++11
...;< together, with the error error: cannot bind ‘std::basic_ostream<char>’ lvalue to ‘std::basic_ostream<char>&&’. this appears to be because when the stream is temporary, the ADL fails, and the above template is not a possibility. any tips?
– of...
Rails 3 execute custom sql query without a model
...o_hash
From the docs:
result = ActiveRecord::Base.connection.exec_query('SELECT id, title, body FROM posts')
result # => #<ActiveRecord::Result:0xdeadbeef>
# Get the column names of the result:
result.columns
# => ["id", "title", "body"]
# Get the record values of the result:
result...
How to set Oracle's Java as the default Java in Ubuntu?
...There are 2 choices for the alternative java (providing /usr/bin/java).
Selection Path Priority Status
------------------------------------------------------------
* 0 /opt/java/jdk1.8.0_05/bin/java 20000 auto mode
1...
Why are dashes preferred for CSS selectors / HTML attributes?
...ops.
Also, using hyphens allows you to take advantage of the |= attribute selector, which selects any element containing the text, optionally followed by a dash:
span[class|="em"] { font-style: italic; }
This would make the following HTML elements have italic font-style:
<span class="em">...
What are bitwise shift (bit-shift) operators and how do they work?
...rs can be applied to integer values (int, long, possibly short and byte or char). In some languages, applying the shift operators to any datatype smaller than int automatically resizes the operand to be an int.
Note that <<< is not an operator, because it would be redundant.
Also note that...
How to see if an object is an array without using reflection?
...d have to check if the object is an instanceof boolean[], byte[], short[], char[], int[], long[], float[], double[], or Object[], if you want to detect all array types.
Also, an int[][] is an instanceof Object[], so depending on how you want to handle nested arrays, it can get complicated.
For the t...
How can Xml Documentation for Web Api include documentation from beyond the main project?
...c. Add the following method below the constructor:
private XPathNavigator SelectSingleNode(string selectExpression)
{
foreach (var navigator in _documentNavigators)
{
var propertyNode = navigator.SelectSingleNode(selectExpression);
if (propertyNode != null)
retur...
Change Bootstrap input focus blue glow
...
you forgot select
– David Morrow
Sep 4 '14 at 16:03
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