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Difference between objectForKey and valueForKey?
What is the difference between objectForKey and valueForKey ?
I looked both up in the documentation and they seemed the same to me.
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Backbone.View “el” confusion
...ou content into the el. So the el serves as a landing place or a container for placing your templated content. Backbone then binds its events to the model data inside of it.
When you create a view you can manipulate the el in four ways using el:, tagName:, className:, and id:. If none of these are...
What is the difference between log4net and ELMAH?
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ELMAH serves a purpose of tracking errors and exceptions for your web applications and allows you to easily log or view those exceptions via many different mechanisms (SQL, RSS, Twitter, files, email, etc.). If you have no built-in exception handling ELMAH will most likely get you ...
What is a web service endpoint?
...by a client application. The same web service can have multiple endpoints, for example in order to make it available using different protocols.
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Quickly reading very large tables as dataframes
... benefit. Your options are:
Using vroom from the tidyverse package vroom for importing data from csv/tab-delimited files directly into an R tibble. See Hector's answer.
Using fread in data.table for importing data from csv/tab-delimited files directly into R. See mnel's answer.
Using read_table ...
How to properly import a selfsigned certificate into Java keystore that is available to all Java app
...this password: changeit
Click Tools > Import Trusted Certificate
Browse for the file mycertificate.pem
Click Import
Click OK for the warning about the trust path.
Click OK when it displays the details about the certificate.
Click Yes to accept the certificate as trusted.
When it asks for an alias...
MySQL Orderby a number, Nulls last
...L has an undocumented syntax to sort nulls last. Place a minus sign (-) before the column name and switch the ASC to DESC:
SELECT * FROM tablename WHERE visible=1 ORDER BY -position DESC, id DESC
It is essentially the inverse of position DESC placing the NULL values last but otherwise the same a...
Purpose of Unions in C and C++
I have used unions earlier comfortably; today I was alarmed when I read this post and came to know that this code
15 Ans...
Pass arguments to Constructor in VBA
...)
Especially useful when you have several classes. Just place a function for each in the module factory and instantiate just by calling factory.CreateClassA(arguments), factory.CreateClassB(other_arguments), etc.
EDIT
As stenci pointed out, you can do the same thing with a terser syntax by avoid...
OpenCV C++/Obj-C: Detecting a sheet of paper / Square Detection
... > contours;
// find squares in every color plane of the image
for (int c = 0; c < 3; c++)
{
int ch[] = {c, 0};
mixChannels(&blurred, 1, &gray0, 1, ch, 1);
// try several threshold levels
const int threshold_level = 2;
for (int l = ...