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How to assign colors to categorical variables in ggplot2 that have stable mapping?
...pulled from separate files and not all factor levels appear in each file.
One way to address this is to create a custom manual colour scale as follows:
#Some test data
dat <- data.frame(x=runif(10),y=runif(10),
grp = rep(LETTERS[1:5],each = 2),stringsAsFactors = TRUE)
#Create a custom ...
Java 8 NullPointerException in Collectors.toMap
The Java 8 Collectors.toMap throws a NullPointerException if one of the values is 'null'. I don't understand this behaviour, maps can contain null pointers as value without any problems. Is there a good reason why values cannot be null for Collectors.toMap ?
...
How to check the differences between local and github before the pull [duplicate]
...ch updates your so-called "remote-tracking branches" - typically these are ones that look like origin/master, github/experiment, etc. that you see with git branch -r. These are like a cache of the state of branches in the remote repository that are updated when you do git fetch (or a successful git...
How do I add more members to my ENUM-type column in MySQL?
...ohn depends. For MariaDB, adding new values at the end of the enum can be done inplace since 10.3.7: mariadb.com/kb/en/library/…
– Felipe Philipp
Sep 18 '19 at 8:17
...
CodeIgniter - accessing $config variable in view
... this -- I was having trouble accessing a config value from a hook. For anyone else, this works great.
– CashIsClay
Jun 21 '13 at 18:22
1
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Best branching strategy when doing continuous integration?
...is developed on a separate branch, with task sub-branches for each change done by individual developer. As features stabilize they get merged to trunk, which you keep reasonably stable and passing all regression tests at all times. As you near the end of your release cycle and all feature branches m...
将 App Inventor 2 项目连接到外部传感器 · App Inventor 2 中文网
...rdware programming more accessible.
The Kit
For sensors, the kit includes one light sensor, some photoresistors, and two ultrasonic sensors. These should suffice for a variety of applications, such as light-following and wall-following. Here is an image of the finished kit:
MOIO board (schematic...
Which Eclipse files belong under version control?
...d .classpath according to the Eclipse documentation).
The goal is that anyone can checkout/update his/her SCM workspace and import the Eclipse project into the Eclipse workspace.
For that, you want to use only relative paths in your .classpath, using linked resources.
Note: it is better if projec...
How to validate an email address using a regular expression?
...tood if studied for a few minutes and is efficient enough for actual use.
One RFC 5322 compliant regex can be found at the top of the page at http://emailregex.com/ but uses the IP address pattern that is floating around the internet with a bug that allows 00 for any of the unsigned byte decimal va...
PowerShell script to return versions of .NET Framework on a machine?
...n]'4.7.2'
528040 = [version]'4.8'
528049 = [version]'4.8'
}
# For One True framework (latest .NET 4x), change the Where-Object match
# to PSChildName -eq "Full":
Get-ChildItem 'HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP' -Recurse |
Get-ItemProperty -name Version, Release -EA 0 |
...