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Use of ~ (tilde) in R programming Language
...".
The myFormula <- part of that line stores the formula in an object called myFormula so you can use it in other parts of your R code.
Other common uses of formula objects in R
The lattice package uses them to specify the variables to plot.
The ggplot2 package uses them to specify panels fo...
Finding duplicate values in MySQL
I have a table with a varchar column, and I would like to find all the records that have duplicate values in this column. What is the best query I can use to find the duplicates?
...
Is there anyway to exclude artifacts inherited from a parent POM?
...to test would be to declare the mail artifact with the version required by ALL-DEPS under the dependencyManagement in the parent pom to force the convergence (although I'm not sure this will solve the scoping problem).
<dependencyManagement>
<dependencies>
<dependency>
...
Bash: Strip trailing linebreak from output
...
If your expected output is a single line, you can simply remove all newline characters from the output. It would not be uncommon to pipe to the 'tr' utility, or to Perl if preferred:
wc -l < log.txt | tr -d '\n'
wc -l < log.txt | perl -pe 'chomp'
You can also use command substit...
HTTP 404 Page Not Found in Web Api hosted in IIS 7.5
...nted a solution that worked for me here.
At the end of the day, I enabled all verbs (verb="*") to the ExtensionlessUrlHandler-Integrated-4.0 handler in my web config.
<system.webServer>
<validation validateIntegratedModeConfiguration="false" />
<modules runAllManagedModulesF...
Is it possible to insert multiple rows at a time in an SQLite database?
...blename'
SELECT 'data1' AS 'column1', 'data2' AS 'column2'
UNION ALL SELECT 'data1', 'data2'
UNION ALL SELECT 'data1', 'data2'
UNION ALL SELECT 'data1', 'data2'
a note on performance
I originally used this technique to efficiently load large datasets from Ruby on Rails. However, as Jaime...
Is Zookeeper a must for Kafka?
... coordination system. So Kafka, Storm, HBase, SolrCloud to just name a few all use Zookeeper to help manage and coordinate.
Kafka is a distributed system and is built to use Zookeeper. The fact that you are not using any of the distributed features of Kafka does not change how it was built. In any ...
Imitating a blink tag with CSS3 animations
I really want to make a piece of text blink the old-school style without using javascript or text-decoration.
9 Answers
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Gem::LoadError for mysql2 gem, but it's already in Gemfile
...eptember 2015 so use the above line in your Gem file and run:
bundle install
You should be good to go
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AngularJS performs an OPTIONS HTTP request for a cross-origin resource
...s-Origin Resource Sharing standard works by adding new HTTP
headers that allow servers to describe the set of origins that are
permitted to read that information using a web browser. Additionally,
for HTTP request methods that can cause side-effects on user data (in
particular; for HTTP meth...