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How to assign colors to categorical variables in ggplot2 that have stable mapping?
...istent color schemes across multiple data frames that are not all obtained by subsetting a single large data frame. Managing the factors levels in multiple data frames can become tedious if they are being pulled from separate files and not all factor levels appear in each file.
One way to address t...
What's the result of += in C and C++?
...part 3:
An assignment operator stores a value in the object designated by the left operand. An
assignment expression has the value of the left operand after the assignment, but is not an
lvalue.
In C++ 5.17.1:
The assignment operator (=) and the compound assignment operators all group ...
How do I remove/delete a virtualenv?
...nvironment. Simply deactivate it and rid your application of its artifacts by recursively removing it.
Note that this is the same regardless of what kind of virtual environment you are using. virtualenv, venv, Anaconda environment, pyenv, pipenv are all based the same principle here.
...
Why do I need to explicitly push a new branch?
... -u origin --all .
Why is this? Isn't a branch a new change to be pushed by default? Why do I need to run the second command?
...
How big should a UIBarButtonItem image be?
I'm looking to create my own custom Sort By Date and Sort By Number buttons that I plan on placing in the navigation bar as the right button.
...
Set 4 Space Indent in Emacs in Text Mode
...in .emacs file:
(custom-set-variables
;; custom-set-variables was added by Custom.
;; If you edit it by hand, you could mess it up, so be careful.
;; Your init file should contain only one such instance.
;; If there is more than one, they won't work right.
'(tab-stop-list (quote (4 8 12 16...
Send and receive messages through NSNotificationCenter in Objective-C?
...ication"
// notifications using the receiveTestNotification: selector. By
// specifying object:nil, we tell the notification center that we are not
// interested in who posted the notification. If you provided an actual
// object rather than nil, the notification center will only not...
What does java:comp/env/ do?
...e
policies might allow you to name users
and organizations/departments by using
names such as "java:user/alice" and
"java:org/engineering".
In the "comp" context, there are two
bindings: "env" and "UserTransaction".
The name "env" is bound to a subtree
that is reserved for the com...
Use of def, val, and var in scala
...ngs, the internal state of a val can be changed but the object referred to by a val cannot. A val is not a constant.
– pferrel
Apr 24 '14 at 21:20
5
...
#define macro for debug printing in C?
...ss of your colleagues or collaborators). See 'The Practice of Programming' by Kernighan and Pike, especially Chapter 8 (see also Wikipedia on TPOP).
This is 'been there, done that' experience — I used essentially the technique described in other answers where the non-debug build does not see the...