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How do I create a category in Xcode 6 or higher?
...; File
Select Objective-C file under Sources in iOS or Mac OS respectively and Click Next
Now under File Type: choose either Category, Protocol, or Extension
PS. Under File Name: whatever you type here will be either the Category, Protocol, or Extension Name.
...
How do I concatenate strings and variables in PowerShell?
...g2 + $string3). With these methods, you can have whitespace (spaces, tabs, and newlines) between the strings, but be sure that (1) each string has a comma/space after it on the same line, (2) you use the back-tick character ` at the end of any empty lines between your code, and (3) if you use -join,...
What are the use-cases for Web Workers? [closed]
... programmed ~2 years ago). You can change one # in a table via input field and a bunch of other numbers in different columns get re-computed in a fairly intensive process.
The old workflow was: Change the #. Go get coffee while JavaScript crunches through changes to other numbers and the web page ...
'git' is not recognized as an internal or external command
...ve an installation of Git for Windows, but when I try to use the git command in Command Prompt, I get the following error:
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Which letter of the English alphabet takes up most pixels?
...our environment. But the fact is, most fonts follow the same conventions, and capital W will be the widest.
Gist with these character widths in a ratio form (W = 100) captured here using this particular example font:
https://gist.github.com/imaurer/d330e68e70180c985b380f25e195b90c
...
Disable Laravel's Eloquent timestamps
...imestamps = false; in every model, or create a BaseModel, define it there, and have all your models extend it instead of eloquent. Just bare in mind pivot tables MUST have timestamps if you're using Eloquent.
Update: Note that timestamps are no longer REQUIRED in pivot tables after Laravel v3.
Up...
Convert data.frame column to a vector?
...a frame is a list. When you subset a data frame using the name of a column and [, what you're getting is a sublist (or a sub data frame). If you want the actual atomic column, you could use [[, or somewhat confusingly (to me) you could do aframe[,2] which returns a vector, not a sublist.
So try run...
Correct format specifier for double in printf
...e before printf receives it1. "%lf" is also acceptable under the current standard -- the l is specified as having no effect if followed by the f conversion specifier (among others).
Note that this is one place that printf format strings differ substantially from scanf (and fscanf, etc.) format stri...
What is the difference between log4net and ELMAH?
...
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 ...
What are the uses for Cross Join?
...
If you have a "grid" that you want to populate completely, like size and color information for a particular article of clothing:
select
size,
color
from
sizes CROSS JOIN colors
Maybe you want a table that contains a row for every minute in the day, and you want to use it to ver...