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Mongoose query where value is not null
...ry The up-to-date doc about it, is here: mongoosejs.com/docs/api.html#query_Query-ne
– zeropaper
Jul 20 '14 at 7:52
Ho...
What's the dSYM and how to use it? (iOS SDK)
... 0x000000018f3c9380 closure #1 in closure #1 in closure #1 in _assertionFailure+ 217984 (_:_:file:line:flags:) + 452
1 libswiftCore.dylib 0x000000018f3c9380 closure #1 in closure #1 in closure #1 in _assertionFailure+ 217984 (_:_:file:line:flags:) + 452
2 libswiftCore.d...
How does Dijkstra's Algorithm and A-Star compare?
...t; but it is a special case of the more general algorithm A*. It is not at all unusual (in fact, probably the norm) for special cases to be discovered first, and then subsequently be generalized .
– Pieter Geerkens
Sep 2 '13 at 15:37
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fork() branches more than expected?
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when i=0
Process_1: Buffered text= 1 dot
Process_2(created by Process_1): Buffered text= 1 dot
when i=1
Process_3(created by Process_1): Inherit 1 buffered dot from Process_1 and prints 1 dot by itself. In total Process_3 prints 2 dots.
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How to fix the uninitialized constant Rake::DSL problem on Heroku?
...ixed my problems and I didn't know what was going on. (Using the rails installer on windows and deploying to heroku, as a complete beginner.)
– Jack V.
Jun 14 '11 at 22:46
1
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How to copy an object in Objective-C
...deep, logical copy. In this, we make a copy of the object, but without actually doing it bit by bit - we want an object that behaves the same for all intents and purposes, but isn't (necessarily) a memory-identical clone of the original - the Objective C manual calls such an object "functionally ind...
How does one generate a random number in Apple's Swift language?
... introduces new easy-to-use random functions for many data types.
You can call the random() method on numeric types.
let randomInt = Int.random(in: 0..<6)
let randomDouble = Double.random(in: 2.71828...3.14159)
let randomBool = Bool.random()
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How to get the last N rows of a pandas DataFrame?
... dataframe df1 and df2 (df1 is vanila dataframe, df2 is indexed by 'STK_ID' & 'RPT_Date') :
3 Answers
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What is the preferred syntax for initializing a dict: curly brace literals {} or the dict() function
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The first version is preferable:
It works for all kinds of keys, so you can, for example, say {1: 'one', 2: 'two'}. The second variant only works for (some) string keys. Using different kinds of syntax depending on the type of the keys would be an unnecessary inconsisten...
How do I specify a single test in a file with nosetests?
I have a file called test_web.py containing a class TestWeb and many methods named like test_something().
6 Answers
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