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Convert data.frame column format from character to factor
...e to the world of R.
mtcars #look at this built in data set
str(mtcars) #allows you to see the classes of the variables (all numeric)
#one approach it to index with the $ sign and the as.factor function
mtcars$am <- as.factor(mtcars$am)
#another approach
mtcars[, 'cyl'] <- as.factor(mtcars[...
C++ project organisation (with gtest, cmake and doxygen)
...rs are the
basis for users to interact with what you offer and must be
installed. This means they have to be in a subdirectory (no-one wants
lots of headers ending up in top-level /usr/include/) and your
headers must be able to include themselves with such a setup.
└── prj
├── inclu...
What is the difference between the Data Mapper, Table Data Gateway (Gateway), Data Access Object (DA
... skills, and I'm curious what are the differences between these patterns? All of them seem like they are the same thing - encapsulate the database logic for a specific entity so the calling code has no knowledge of the underlying persistence layer. From my brief research all of them typically impl...
How to select a single field for all documents in a MongoDB collection?
... include several fields. In the following operation, find() method returns all documents that match the query. In the result set, only the item and qty fields and, by default, the _id field return in the matching documents.
db.inventory.find( { type: 'food' }, { item: 1, qty: 1 } )
In this example ...
Where is the warnings screen option in Android Studio?
...dow that pops up select how much of your project you want to inspect (I usually do Whole Project, but you might want to select a specific module), then click okay.
Android Studio will work for a bit, then the inspection window will pop up from the bottom with a list of results, subdivided by inspe...
Can we set a Git default to fetch all tags during a remote pull?
...that are downloaded from the
remote repository are fetched and stored locally.
If that default statement is not a restriction, then you can also try
git pull --force
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Select element based on multiple classes
...ces between them):
.class1.class2 {
/* style here */
}
This selects all elements with class1 that also have class2.
In your case:
li.left.ui-class-selector {
}
Official documentation : CSS2 class selectors.
As akamike points out a problem with this method in Internet Explorer 6 you mi...
Xcode Project vs. Xcode Workspace - Differences
... linker flags, and they define which files (source code and resources) actually belong to a product. When you build/run, you always select one specific target.
It is likely that you have a few targets that share code and resources. These different targets can be slightly different versions of an ap...
Do I need a Global.asax.cs file at all if I'm using an OWIN Startup.cs class and move all configurat
...
Startup.Configuration gets called slightly later than Application_Start, but I don't think the difference will matter much in most cases.
I believe the major reasons we kept the other code in Global.asax are:
Consistency with previous versions of MVC...
Difference between make and build in Android Studio
...ed. Others are seldom used.
It is the same as IntelliJ Idea.
Compile All the source files in the specified scope are compiled. The scope in this case may be a file, a package, etc.
Make Project All the source files in the entire project that have been modified since the last compilation a...