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How do I make a list of data frames?
...is is super-easy, the base function split() does it for you. You can split by a column (or columns) of the data, or by anything else you want
mt_list = split(mtcars, f = mtcars$cyl)
# This gives a list of three data frames, one for each value of cyl
This is also a nice way to break a data frame i...
bool operator ++ and --
...
And unsurprisingly...
5.3.2-2
The operand of prefix -- is modified
by subtracting 1. The operand shall
not be of type bool. The requirements
on the operand of prefix -- and the
properties of its result are otherwise
the same as those of prefix ++. [Note:
For postfix increment and d...
Do I need to disable NSLog before release Application?
...eplacer' before the compiler is called. It replaces anything you '#define' by what follows the #define statement.
#define NSLog(...);
The (...) stands for 'anything' between the brackets (). Mind also the ; at the end. This is not strictly necessary as the compiler will optimize this away, but I ...
How to .gitignore files recursively
... [...] git treats the pattern as a shell glob suitable for
consumption by fnmatch(3) with the FNM_PATHNAME flag: wildcards in
the pattern will not match a / in the pathname.
So, this clearly stands that there is no way to specify a certain amount of directories between two strings, like be...
How to concatenate multiple lines of output to one line?
...ine, effectively replacing each "\n" with "\" " (end with " followed by space)?
11 Answers
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Mock framework vs MS Fakes frameworks
...a values for methods or properties that will be asked of your test doubles by the method under test. For example, when my method under test calls the DoesStudentExist() method of the IStudentRepository test double, I want it to return true.
The idea of stubs in NMock and MS fakes is the same, but ...
What's the difference between HEAD, working tree and index, in Git?
...eflect the current position of project development.
(note: as commented by Timo Huovinen, those arrows are not what the commits point to, it's the workflow order, basically showing arrows as 1 -> 2 -> 3 -> 4 where 1 is the first commit and 4 is the last)
Now we know what is happening in...
Branch from a previous commit using Git
... the branch via a hash:
git branch branchname <sha1-of-commit>
Or by using a symbolic reference:
git branch branchname HEAD~3
To checkout the branch when creating it, use
git checkout -b branchname <sha1-of-commit or HEAD~3>
...
Keep only date part when using pandas.to_datetime
I use pandas.to_datetime to parse the dates in my data. Pandas by default represents the dates with datetime64[ns] even though the dates are all daily only.
I wonder whether there is an elegant/clever way to convert the dates to datetime.date or datetime64[D] so that, when I write the data t...
Download Github pull request as unified diff
...
Judging by what these return and the the links in the docs at developer.github.com/v3/media/… , the .diff URL gives a straight diff to the default branch based on git-diff git-scm.com/docs/git-diff output, and the .patch URL gives ...