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Counting the number of True Booleans in a Python List

... 2 This is actually more efficient than sum, as well as being more explicit about the intent, so there's no reason to use sum: In [1]: import random In [2]: x = [random.choice([True, False]) for i in range(100)] In [3]: %timeit x.count(True) 970 ns ± 41.1 ns per loop (mean ± std. dev. of 7 ru...
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When to use a key/value store such as Redis instead/along side of a SQL database?

...s about key/value stores such as Redis but I can't seem to figure out when it's time to use it in an application. 4 Answers...
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Linq style “For Each” [duplicate]

...ult as the above use of ToList, but is (in theory) more efficient, because it streams the values directly to the delegate. share | improve this answer | follow ...
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Postgresql: Scripting psql execution with password

How can I call psql so that it doesn't prompt for a password ? 15 Answers 15 ...
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Copy a stream to avoid “stream has already been operated upon or closed”

I'd like to duplicate a Java 8 stream so that I can deal with it twice. I can collect as a list and get new streams from that; ...
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What is memoization and how can I use it in Python?

...t started Python and I've got no idea what memoization is and how to use it. Also, may I have a simplified example? 13 An...
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Does ruby have real multithreading?

... Updated with Jörg's Sept 2011 comment You seem to be confusing two very different things here: the Ruby Programming Language and the specific threading model of one specific implementation of the Ruby Programming Language. There ...
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Why use a prime number in hashCode?

...rge enough prime that the number of buckets is unlikely to be divisible by it (and in fact, modern java HashMap implementations keep the number of buckets to a power of 2). share | improve this answ...
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Tracking CPU and Memory usage per process

I suspect that one of my applications eats more CPU cycles than I want it to. The problem is - it happens in bursts, and just looking at the task manager doesn't help me as it shows immediate usage only. ...
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Should I use single or double colon notation for pseudo-elements?

... support the single-colon notation (e.g. :after ) for backwards compatibility, should I use solely the single-colon notation and when IE8's market share drops to a negligible level go back and find/replace in my code base? Or should I include both: ...