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Difference between volatile and synchronized in Java
... am wondering at the difference between declaring a variable as volatile and always accessing the variable in a synchronized(this) block in Java?
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How to create an installer for a .net Windows Service using Visual Studio
...click your services .cs file. It should bring up a screen that is all gray and talks about dragging stuff from the toolbox.
Then right click on the gray area and select add installer. This will add an installer project file to your project.
Then you will have 2 components on the design view of the P...
What is /dev/null 2>&1?
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>> /dev/null redirects standard output (stdout) to /dev/null, which discards it.
(The >> seems sort of superfluous, since >> means append while > means truncate and write, and either appending to or writing to /dev/null has the same n...
Float vs Decimal in ActiveRecord
...ation defines floats in binary format. Basically, it stores sign, fraction and exponent to represent a Float. It's like a scientific notation for binary (something like +1.43*10^2). Because of that, it is impossible to store fractions and decimals in Float exactly.
That's why there is a Decimal for...
How do I replace NA values with zeros in an R dataframe?
I have a data frame and some columns have NA values.
21 Answers
21
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What is 'Currying'?
I've seen references to curried functions in several articles and blogs but I can't find a good explanation (or at least one that makes sense!)
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Git branch strategy for small dev team [closed]
We have a web app that we update and release almost daily. We use git as our VCS, and our current branching strategy is very simple and broken: we have a master branch and we check changes that we 'feel good about' into it. This works, but only until we check in a breaking change.
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PostgreSQL - fetch the row which has the Max value for a column
...that contains records with columns for time_stamp, usr_id, transaction_id, and lives_remaining. I need a query that will give me the most recent lives_remaining total for each usr_id
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What is the most useful script you've written for everyday life? [closed]
...of each other as an o, two 0 keystrokes within 700 MS of each other as a 0 and ignore the rest; so I could use my laptop before I get around to replacing the keyboard.
Wow; I didn't know this would be so popular :p
As for how - Microsoft exposes a nice little API feature called Hooks.
Using that ...
How to determine if a number is a prime with regex?
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You said you understand this part, but just to emphasize, the String generated has a length equal to the number supplied. So the string has three characters if and only if n == 3.
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The first part of the regex says, "any character, zero or o...