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How to prevent ifelse() from turning Date objects into numeric objects
... to manipulate a date vector. I expected the result to be of class Date , and was surprised to get a numeric vector instead. Here is an example:
...
What do I need to do to get Internet Explorer 8 to accept a self signed certificate?
...Options.
Select Security➞Trusted sites➞Sites.
Confirm the URL matches, and click “Add” then “Close”.
Close the “Internet Options” dialog box with either “OK” or “Cancel”.
Refresh the current page.
When told “There is a problem with this website's security certificate.”, c...
Are (non-void) self-closing tags valid in HTML5?
...ich leads to <br /> meaning <br>> (i.e. <br>&gt;) and <title/hello/ meaning <title>hello</title>). This is an SGML rule that browsers did a very poor job of supporting, and the spec advises authors to avoid the syntax.
In XHTML, <foo /> means <foo>...
What's the “big idea” behind compojure routes?
I'm new to Clojure and have been using Compojure to write a basic web application. I'm hitting a wall with Compojure's defroutes syntax, though, and I think I need to understand both the "how" and the "why" behind it all.
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How can I merge two commits into one if I already started rebase?
...base todo list, that is into a commit on a previous line. Changing the command on your todo list’s very first line to squash will always produce this error as there is nothing for the first commit to squash into.
The Fix
First get back to where you started with
$ git rebase --abort
Say your h...
Type erasure techniques
... erasure techniques in C++ are done with function pointers (for behaviour) and void* (for data). The "different" methods simply differ in the way they add semantic sugar. Virtual functions, e.g., are just semantic sugar for
struct Class {
struct vtable {
void (*dtor)(Class*);
vo...
What is sr-only in Bootstrap 3?
... @Christophe I would still recommend that article for understanding the concept. Even though it doesn't explain the problems with rtl content it does list different techniques which also includes clipping
– katranci
Jan 20 '14 at 12:02
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Why are #ifndef and #define used in C++ header files?
...his case HEADERFILE_H) is defined. Then if it's not defined, it defines it and continues to the rest of the page.
When the code is included again, the first ifndef fails, resulting in a blank file.
That prevents double declaration of any identifiers such as types, enums and static variables.
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Why doesn't Java allow overriding of static methods?
...nce of a class. The point of polymorphism is that you can subclass a class and the objects implementing those subclasses will have different behaviors for the same methods defined in the superclass (and overridden in the subclasses). A static method is not associated with any instance of a class so ...
How do I specify different layouts for portrait and landscape orientations?
...to specify two separate layout xml files for an activity, one for Portrait and one for Landscape. I've not been to find any information on how to do that though. How do I specify for each activity which xml file is it's portrait layout and which is the Landscape layout?
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