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How to track untracked content?
...plugins/open_flash_chart_2 starts out as an independent Git repository. Usually such sub-repositories are ignored, but if you tell git add to explicitly add it, then it will create an gitlink entry that points to the sub-repository’s HEAD commit instead of adding the contents of the directory. It ...
Scala: List[Future] to Future[List] disregarding failed futures
...ures to a Future of List. I'm using Playframework, so ultimately, what I really want is a Future[Result] , but to make things simpler, let's just say Future[List[Int]] The normal way to do this would be to use Future.sequence(...) but there's a twist... The list I'm given usually has around 10-...
How can I rename a field for all documents in MongoDB?
...above are: { upsert:false, multi:true }. You need the multi:true to update all your records.
Or you can use the former way:
remap = function (x) {
if (x.additional){
db.foo.update({_id:x._id}, {$set:{"name.last":x.name.additional}, $unset:{"name.additional":1}});
}
}
db.foo.find().forEach...
Determine if 2 lists have the same elements, regardless of order? [duplicate]
... helper function. Note that it will be quite slow (O(n²)) and should generally not be used outside of the esoteric case of unhashable and unsortable elements.
def equal_ignore_order(a, b):
""" Use only when elements are neither hashable nor sortable! """
unmatched = list(b)
for element...
How to use the PI constant in C++
...
On some (especially older) platforms (see the comments below) you might need to
#define _USE_MATH_DEFINES
and then include the necessary header file:
#include <math.h>
and the value of pi can be accessed via:
M_PI
In my math....
What's the difference between utf8_general_ci and utf8_unicode_ci?
...languages or characters.
On modern servers, this performance boost will be all but negligible. It was devised in a time when servers had a tiny fraction of the CPU performance of today's computers.
Benefits of utf8mb4_unicode_ci over utf8mb4_general_ci
utf8mb4_unicode_ci, which uses the Unicode r...
Stripping everything but alphanumeric chars from a string in Python
What is the best way to strip all non alphanumeric characters from a string, using Python?
11 Answers
...
What does the “yield” keyword do?
... list, you can read its items one by one. Reading its items one by one is called iteration:
>>> mylist = [1, 2, 3]
>>> for i in mylist:
... print(i)
1
2
3
mylist is an iterable. When you use a list comprehension, you create a list, and so an iterable:
>>> mylist = [...
Function return value in PowerShell
...
PowerShell has really wacky return semantics - at least when viewed from a more traditional programming perspective. There are two main ideas to wrap your head around:
All output is captured, and returned
The return keyword really just indi...
Python error “ImportError: No module named”
Python is installed in a local directory.
28 Answers
28
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