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Why would a static nested interface be used in Java?
... above example is redundant (a nested interface is automatically "static") and can be removed with no effect on semantics; I would recommend it be removed. The same goes for "public" on interface methods and "public final" on interface fields - the modifiers are redundant and just add clutter to the...
How do you delete a column by name in data.table?
...the following will remove column foo from the data.table df3:
# Method 1 (and preferred as it takes 0.00s even on a 20GB data.table)
df3[,foo:=NULL]
df3[, c("foo","bar"):=NULL] # remove two columns
myVar = "foo"
df3[, (myVar):=NULL] # lookup myVar contents
# Method 2a -- A safe idiom for excl...
Why is volatile needed in C?
...ther thread running that also uses the variable; or when there's a signal handler that might change the value of the variable.
Let's say you have a little piece of hardware that is mapped into RAM somewhere and that has two addresses: a command port and a data port:
typedef struct
{
int command;...
Get current URL with jQuery?
I am using jQuery. How do I get the path of the current URL and assign it to a variable?
32 Answers
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How do I join two SQLite tables in my Android application?
I have an Android project that has a database with two tables: tbl_question and tbl_alternative .
4 Answers
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Rename a file in C#
... not work when file names differ only in letter case. For example file.txt and File.txt
– SepehrM
Jul 6 '14 at 20:31
2
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Check if $_POST exists
I'm trying to check whether a $_POST exists and if it does, print it inside another string, if not, don't print at all.
14 ...
What is the difference between SIGSTOP and SIGTSTP?
Just wondering about the difference between SIGSTOP and SIGTSTP signals.
3 Answers
3...
Couldn't connect to server 127.0.0.1:27017
...mongodb is terminating because there is an old lock file.
If you are not and were not running with journaling, remove the lock file, run repair, and start mongodb again.
If you are or were running with journaling turned on, see the relevant Mongo DB docs. Note that they say "If you are running wi...
Python OpenCV2 (cv2) wrapper to get image size?
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cv2 uses numpy for manipulating images, so the proper and best way to get the size of an image is using numpy.shape. Assuming you are working with BGR images, here is an example:
>>> import numpy as np
>>> import cv2
>>> img = cv2.imread('foo.jpg')
&g...