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What is the purpose of “!” and “?” at the end of method names?
...e object while Enumerable#sort! sorts it in place.
In Rails, ActiveRecord::Base#save returns false if saving failed, while ActiveRecord::Base#save! raises an exception.
Kernel::exit causes a script to exit, while Kernel::exit! does so immediately, bypassing any exit handlers.
Methods ending in ? re...
Python vs Cpython
...mplement new features; Python-the-language development uses CPython as the base; other implementations follow.
What about Jython, etc.?
Jython, IronPython and PyPy are the current "other" implementations of the Python programming language; these are implemented in Java, C# and RPython (a subset of P...
use Winmerge inside of Git to file diff
..." "$(cygpath -aw "$2")"
"$PROGRAMFILES/WinMerge/WinMergeU.exe" -e -ub -dl "Base" -dr "Mine" "$(cygpath -aw "$1")" "$(cygpath -aw "$2")"
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What is href=“#” and why is it used?
...n annoying jump to the top of the page, but in the case of sites using <base>, <a href="#"> is handled as <a href="[base href]/#">, resulting in an unexpected navigation. If any logable errors are being generated, you won't see them in the latter case unless you enable persistent ...
Float vs Decimal in ActiveRecord
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So if I understand correctly, float is in base-2 whereas decimal is in base-10? What would be a good use for float? What does your example do, and demonstrate?
– Jonathan Allard
Dec 15 '11 at 20:30
...
Getting only Month and Year from SQL DATE
...]
FROM
<your_table>
This gets the number of whole months from a base date (0) and then adds them to that base date. Thus rounding Down to the month in which the date is in.
NOTE: In SQL Server 2008, You will still have the TIME attached as 00:00:00.000
This is not exactly the same as "r...
How to download an entire directory and subdirectories using wget?
...ning anymore and I am only able to access the files through a browser. The base URLs for all the files is the same like
8 ...
What's the difference between getPath(), getAbsolutePath(), and getCanonicalPath() in Java?
....txt
C:\projects\sandbox\trunk\file.txt
So, getPath() gives you the path based on the File object, which may or may not be relative; getAbsolutePath() gives you an absolute path to the file; and getCanonicalPath() gives you the unique absolute path to the file. Notice that there are a huge number ...
How to use the 'sweep' function
...a weighted covariance matrix as per @James King's example.
Here's another based on a current project:
set.seed(1)
## 2x2x2 array
a1 <- array(as.integer(rnorm(8, 10, 5)), dim=c(2, 2, 2))
## 'element-wise' sum of matrices
## weights = 1
rowSums(a1, dims=2)
## weights
w1 <- c(3, 4)
## a1[, , 1]...
What is a race condition?
...rent.atomic, concurrent data structures, proper synchronization, and actor based concurrency will help.
The best resource for concurrency is JCIP. You can also get some more details on above explanation here.
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