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mongodb group values by multiple fields
... $slice just off the basic aggregation result. For "large" results, run parallel queries instead for each grouping ( a demonstration listing is at the end of the answer ), or wait for SERVER-9377 to resolve, which would allow a "limit" to the number of items to $push to an array.
db.books.aggregate(...
Finding a substring within a list in Python [duplicate]
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All the answers work but they always traverse the whole list. If I understand your question, you only need the first match. So you don't have to consider the rest of the list if you found your first match:
mylist = ['abc123'...
Why does GCC generate such radically different assembly for nearly the same C code?
...e(). I'll spare you the assembly, but it is identical - register names and all.
Step 2: Mathematical reduction: x + (y ^ x) = y
sign can only take one of two values, 0 or 0x80000000.
When x = 0, then x + (y ^ x) = y then trivial holds.
Adding and xoring by 0x80000000 is the same. It flips the sign...
Does Swift support reflection?
...s to me it's just a hack to enable debugging in Xcode. Protocol Mirror actually quotes the word IDE several times.
– Sulthan
Jun 6 '14 at 7:50
7
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UTF-8: General? Bin? Unicode?
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This doesn't really answer the question in depth though. What is the difference between these collations exactly?
– Pekka
Apr 2 '11 at 22:34
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Use find command but exclude files in two directories
...k for files with the name ending in _peaks.bed
! -path "./tmp/*" - Exclude all results whose path starts with ./tmp/
! -path "./scripts/*" - Also exclude all results whose path starts with ./scripts/
Testing the Solution:
$ mkdir a b c d e
$ touch a/1 b/2 c/3 d/4 e/5 e/a e/b
$ find . -type f ! -p...
Fixed size queue which automatically dequeues old values upon new enques
...ur own queue, just use the inherited one. If you do as you do, you can actually do nothing else with the queue values, all other functions but your new Enqueue will still call the original queue. In other words, although this answer is marked as accepted, it's completely and utterly broken.
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Getting list of parameter names inside python function [duplicate]
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Well we don't actually need inspect here.
>>> func = lambda x, y: (x, y)
>>>
>>> func.__code__.co_argcount
2
>>> func.__code__.co_varnames
('x', 'y')
>>>
>>> def func2(x,y=3):
... print(...
What's the meaning of exception code “EXC_I386_GPFLT”?
...hich is the x86's way to tell you that "you did something that you are not allowed to do". It typically DOESN'T mean that you access out of memory bounds, but it could be that your code is going out of bounds and causing bad code/data to be used in a way that makes for an protection violation of som...
Removing Data From ElasticSearch
...lasticSearch. I have deleted my indexes. However, that doesn't seem to actually remove the data itself. The other stuff I've seen points to the Delete by Query feature. However, I'm not even sure what to query on. I know my indexes. Essentially, I'd like to figure out how to do a
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