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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...
Difference between 3NF and BCNF in simple terms (must be able to explain to an 8-year old)
... have read the quote :
data depends on the key [1NF], the whole key [2NF] and nothing but the key [3NF] .
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How do I replace NA values with zeros in an R dataframe?
I have a data frame and some columns have NA values.
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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.
.?
The first part of the regex says, "any character, zero or o...
How to upload a file in Django? [closed]
...xample about this. I spent over 2 hours to dig up all the pieces to understand how this works. With that knowledge I implemented a project that makes possible to upload files and show them as list. To download source for the project, visit https://github.com/axelpale/minimal-django-file-upload-exam...
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...
Difference between Xcode version (CFBundleShortVersionString) and build (CFBundleVersion)
...you might tack something else on to the CFBundleVersion, maybe another dot and integer.
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Fastest way to iterate over all the chars in a String
... as byte[] by default.
SECOND UPDATE: As of 2016-10-25, on my AMDx64 8core and source 1.8, there is no difference between using 'charAt' and field access. It appears that the jvm is sufficiently optimized to inline and streamline any 'string.charAt(n)' calls.
THIRD UPDATE: As of 2020-09-07, on my Ry...
Unbound classpath container in Eclipse
I have checked out a project using Subversive for Eclipse and I am getting the following errors:
13 Answers
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