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Exploring Docker container's file system
I've noticed with docker that I need to understand what's happening inside a container or what files exist in there. One example is downloading images from the docker index - you don't have a clue what the image contains so it's impossible to start the application.
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How to save a data.frame in R?
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There is also dump and files created would be source()-ed, although the help(dump) page says save is "safer".
– IRTFM
Dec 1 '11 at 17:44
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Undoing accidental git stash pop
...ink there are always two commits for a stash, since it preserves the index and the working copy (so often the index commit will be empty). Then git show them to see the diff and use patch -R to unapply them.
share
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How do I remove leading whitespace in Python?
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The lstrip() method will remove leading whitespaces, newline and tab characters on a string beginning:
>>> ' hello world!'.lstrip()
'hello world!'
Edit
As balpha pointed out in the comments, in order to remove only spaces from the beginning of the string, lstrip(' ') s...
How to append something to an array?
...to the length property. The interpreter does an amazing job at that itself and it will not make any difference in The Real World whether you optimize it away or not. If your array becomes so huge that optimizing .length would actually help, most probably an array is not the right data structure anym...
Default initialization of std::array?
...zed (C++11 §8.5/11). That includes objects of type std::array<T, N> and T[N].
Be aware that there are types for which default initialization has no effect and leaves the object's value indeterminate: any non-class, non-array type (§8.5/6). Consequently, a default-initialized array of object...
How do negative margins in CSS work and why is (margin-top:-5 != margin-bottom:5)?
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Negative margins are valid in css and understanding their (compliant) behaviour is mainly based on the box model and margin collapsing. While certain scenarios are more complex, a lot of common mistakes can be avoided after studying the spec.
For instance, r...
Introducing FOREIGN KEY constraint may cause cycles or multiple cascade paths - why?
I've been wrestling with this for a while and can't quite figure out what's happening. I have a Card entity which contains Sides (usually 2) - and both Cards and Sides have a Stage. I'm using EF Codefirst migrations and the migrations are failing with this error:
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Minimizing NExpectation for a custom distribution in Mathematica
...a minimum requires either to set the first derivative of the function zero and solve for a solution. Since your function is quite complicated (and probably not differentiable), the second possibility is to do a numerical minimization, which requires many evaluations of your function. Ergo, it is ver...
HttpClient.GetAsync(…) never returns when using await/async
... misusing the API.
Here's the situation: in ASP.NET, only one thread can handle a request at a time. You can do some parallel processing if necessary (borrowing additional threads from the thread pool), but only one thread would have the request context (the additional threads do not have the reque...