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Difference between reduce and foldLeft/fold in functional programming (particularly Scala and Scala
...plicit val sc = new SparkContext(conf)
val range = ('a' to 'z').map(_.toString)
val rdd = sc.parallelize(range)
println(range.reduce(_ + _))
println(rdd.reduce(_ + _))
println(rdd.fold("")(_ + _))
}
Print out:
abcdefghijklmnopqrstuvwxyz
abcghituvjklmwxyzqrsdefnop
defghinopjklmqrst...
Can I mask an input text in a bat file?
...ate the "echo -n" command from the bash shell. It sets passwd to an empty string as an irrelevant side effect and doesn't wait for input since it's taking its input from the nul: device.
The "for /f "delims=" %%i in ('cscript /nologo getpwd.vbs') do set passwd=%%i" statement is the trickiest bit. ...
Converting user input string to regular expression
...r expression tester in HTML and JavaScript. The user will enter a regex, a string, and choose the function they want to test with (e.g. search, match, replace, etc.) via radio button and the program will display the results when that function is run with the specified arguments. Naturally there will...
Google Maps Android API v2 Authorization failure
...equired.
Under the Manifest file I replaced the old API KEY value with the
string shortcut created by this new XML file:
android:value="@string/google_maps_key", instead of stating the KEY
directly.
Finally, remove the new MapActivity, but keep the xml file that was
created in that process.
Note: ...
Using braces with dynamic variable names in PHP
...
Overview
In PHP, you can just put an extra $ in front of a variable to make it a dynamic variable :
$$variableName = $value;
While I wouldn't recommend it, you could even chain this behavior :
$$$$$$$$DoNotTryThisAtHomeKids = $value;
You can but are not forced...
What's the deal with a leading underscore in PHP class methods?
.... In some older classes you'll see /**private*/ __foo() { to give it some extra weight.
I've never heard of developers prefacing all their methods with underscores, so I can't begin to explain what causes that.
share
...
phonegap open link in browser
... not able to get links to open in the default browser app cross-platform.
Extra credit
Here's an example (live) click handler for the links:
document.addEventListener('click', function (e) {
if (e.target.tagName === 'A' &&
e.target.href.match(/^https?:\/\//)) {
e.preve...
Setting environment variables for accessing in PHP when using Apache
...
in xampp on windows the file will be C:\xampp\apache\conf\extra\httpd-vhosts.conf
– Dung
Apr 3 '17 at 19:09
...
Using generic std::function objects with member functions in one class
...tip: member function pointer can be implicitly cast to std::function, with extra this as it's first parameter, like std::function<void(Foo*, int, int)> = &Foo::doSomethingArgs
– landerlyoung
Nov 25 '19 at 6:44
...
How should I copy Strings in Java?
...kup variable still contains the original value "hello" (this is because of String's immutability right?).
5 Answers
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