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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 ...
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[...
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...
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...
Why does += behave unexpectedly on lists?
...
The general answer is that += tries to call the __iadd__ special method, and if that isn't available it tries to use __add__ instead. So the issue is with the difference between these special methods.
The __iadd__ special method is for an in-place addition, that i...
Relationship between SciPy and NumPy
SciPy appears to provide most (but not all [1]) of NumPy's functions in its own namespace. In other words, if there's a function named numpy.foo , there's almost certainly a scipy.foo . Most of the time, the two appear to be exactly the same, oftentimes even pointing to the same function object.
...
How does Python's super() work with multiple inheritance?
...ave trouble
understanding the super() function (new style classes) especially when it comes to multiple inheritance.
16 A...