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Selecting data frame rows based on partial string match in a column
...matching. Here's an example with the mtcars dataset, where we are matching all rows where the row names includes "Merc":
mtcars[grep("Merc", rownames(mtcars)), ]
mpg cyl disp hp drat wt qsec vs am gear carb
# Merc 240D 24.4 4 146.7 62 3.69 3.19 20.0 1 0 4 2
# Merc 230 ...
What is the difference between ? and Object in Java generics?
...is right way to go to use ResponseEntity<?> on controller level for all my controller functions?
– Irakli
Nov 25 '16 at 7:38
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Determine which JAR file a class is from
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Yes. It works for all classes except classes loaded by bootstrap classloader. The other way to determine is:
Class klass = String.class;
URL location = klass.getResource('/' + klass.getName().replace('.', '/') + ".class");
As notnoop pointe...
How do I install a module globally using npm?
I recently installed Node.js and npm module on OSX and have a problem with the settings I think:
7 Answers
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Chrome extension: accessing localStorage in content script
...xtension context, so you don't need content scripts or messaging. You can call localStorage directly from the options page or use chrome.extension.getBackgroundPage from the options page.
– Mohamed Mansour
Jul 23 '11 at 12:43
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Can you resolve an angularjs promise before you return it?
...Nizet's Plunkr but refactored to work within the context of what was originally asked (i.e. a function call to service) and actually on site.
Inside the service...
function getSomething(id) {
// There will always be a promise so always declare it.
var deferred = $q.defer();
if (Cache[i...
What exactly is Heroku?
I just started learning Ruby on rails and I was wondering what Heroku really is? I know that its a cloud that helps us to avoid using servers? When do we actually use it?
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Log4Net, how to add a custom field to my logging
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@DumbDev, usually you will use the Thread context. The GlobalContext is useful to set properties that do not change very often.
– Marcelo De Zen
Mar 10 '15 at 19:06
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Why can't non-default arguments follow default arguments?
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All required parameters must be placed before any default arguments. Simply because they are mandatory, whereas default arguments are not. Syntactically, it would be impossible for the interpreter to decide which values match...
Java Enum Methods - return opposite direction enum
... method that returns the opposite direction (the following is not syntactically correct, i.e, enums cannot be instantiated, but it illustrates my point). Is this possible in Java?
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