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`levels
...answers here are good, but they are missing an important point. Let me try and describe it.
R is a functional language and does not like to mutate its objects. But it does allow assignment statements, using replacement functions:
levels(x) <- y
is equivalent to
x <- `levels<-`(x, y)
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Find all files with name containing string
I have been searching for a command that will return files from the current directory which contain a string in the filename. I have seen locate and find commands that can find files beginning with something first_word* or ending with something *.jpg .
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Why did my Git repo enter a detached HEAD state?
...t 2.23 (August 2019), you don't have to use the confusing git checkout command anymore.
git switch can also checkout a branch, and get a detach HEAD, except:
it has an explicit --detach option
To check out commit HEAD~3 for temporary inspection or experiment without creating a new branch:
g...
Prevent multiple instances of a given app in .NET?
...way to prevent multiple instances of an app from running at the same time? And if there's no "best" technique, what are some of the caveats to consider with each solution?
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How to get hosting Activity from a view?
I have an Activity with 3 EditText s and a custom view which acts a specialised keyboard to add information into the EditText s.
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Java Enum definition
...similar in my C# port of ProtocolBuffers. There are "messages" (immutable) and "builders" (mutable, used to build a message) - and they come as pairs of types. The interfaces involved are:
public interface IBuilder<TMessage, TBuilder>
where TMessage : IMessage<TMessage, TBuilder>
w...
Doctrine and composite unique keys
...umn names, not field names. So you have to convert camelCase to snake_case and append _id for associations, because that's how Doctrine generates column names.
– gronostaj
Mar 6 '18 at 13:35
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JavaScript function order: why does it matter?
...further down the page than the call to it. However, my page is for a game, and no functions are called until the whole thing has downloaded. So why does the order functions appear in my code matter?
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Java dynamic array sizes?
...e it needs to grow in size. When it does you'll have to allocate a new one and copy the data from the old to the new:
int[] oldItems = new int[10];
for (int i = 0; i < 10; i++) {
oldItems[i] = i + 10;
}
int[] newItems = new int[20];
System.arraycopy(oldItems, 0, newItems, 0, 10);
oldItems = ...
How to get scrollbar position with Javascript?
...iew is. My guess is that I have to detect where the thumb on the track is, and then the height of the thumb as a percentage of the total height of the track. Am I over-complicating it, or does JavaScript offer an easier solution than that? Any ideas code-wise?
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