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Convert a list to a data frame
...hich in turn yields FALSE as its default.
Assuming your list of lists is called l:
df <- data.frame(matrix(unlist(l), nrow=length(l), byrow=T))
The above will convert all character columns to factors, to avoid this you can add a parameter to the data.frame() call:
df <- data.frame(matrix(unl...
Correct way to detach from a container without stopping it
...aseimage-docker/#intro)
If you want a container that run in detached mode all the time, i suggest you use
docker run -d foo
With an ssh server on the container. (easiest way is to follow the dockerizing openssh tutorial https://docs.docker.com/engine/examples/running_ssh_service/)
Or you can ju...
When to use SELECT … FOR UPDATE?
... a DML query creates a copy of the record (in one or another way) and generally readers do not block writers and vice versa. For these databases, a SELECT FOR UPDATE would come handy: it would lock either SELECT or the DELETE query until another session commits, just as SQL Server does.
When sh...
Change URL and redirect using jQuery
... Mathias BynensMathias Bynens
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What is the difference between a regular string and a verbatim string?
... = @"C:\myfolder\myfile.txt";
The @ symbol means to read that string literally, and don't interpret control characters otherwise.
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Why can tuples contain mutable items?
...way to detect this.
Another insight is that Python's containers don't actually contain anything. Instead, they keep references to other objects. Likewise, Python's variables aren't like variables in compiled languages; instead the variable names are just keys in a namespace dictionary where they ...
What are differences between AssemblyVersion, AssemblyFileVersion and AssemblyInformationalVersion?
...erated by MSBuild" - Why? You just went on to explain a good reason to manually control it :)
– mo.
Jan 4 '13 at 17:50
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how do I query sql for a latest record date for each user
... row number of 1, so the results may be inconsistent. But as long as you really don't care, then this shouldn't be a problem. This can be solved if you add the PK after the date. For example: order by date desc, id desc).
– Andrew
Apr 26 '19 at 21:40
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How many GCC optimization levels are there?
..., the default if no optimization level is specified)
-O1 (optimize minimally)
-O2 (optimize more)
-O3 (optimize even more)
-Ofast (optimize very aggressively to the point of breaking standard compliance)
-Og (Optimize debugging experience. -Og enables optimizations that do not interfere...
How do I Convert DateTime.now to UTC in Ruby?
...ok.
– DanSingerman
Apr 16 '09 at 11:32
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Oh sweet. So whats the difference between Date, Time an...