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Does name length impact performance in Redis?
...example key you give is for a set, set lookup methods are O(1). The more complex operations on a set (SDIFF, SUNION, SINTER) are O(N). Chances are that populating $userId was a more expensive operation than using a longer key.
Redis comes with a benchmark utility called redis-benchmark, if you m...
The Concept of 'Hold space' and 'Pattern space' in sed
... pattern space if you want to do something with it. For example, the print command p prints the pattern space only. Likewise, s operates on the pattern space.
Here is an example:
sed -n '1!G;h;$p'
(the -n option suppresses automatic printing of lines)
There are three commands here: 1!G, h and $...
Difference between framework and static library in xcode4, and how to call them
...s over static libraries is that they act as a neat way of packaging up the compiled library binary and any related headers. They can be dropped into your project (just like the SDK's built-in frameworks like Foundation and UIKit) and they should just work (most of the time).
Most frameworks contain...
Count, size, length…too many choices in Ruby?
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Why is Maven downloading the maven-metadata.xml every time?
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Named regular expression group “(?Pregexp)”: what does “P” stand for?
... end of
this year. I hope that Python and Perl can co-exist in years to come;
cross-pollination can be good for both languages. (I believe Larry
had a good look at Python when he added objects to Perl 5; O'Reilly
publishes books about both languages.)
As you may know, Python 1.5 adds ...
Boolean operators && and ||
...f.
The functions all and any are often used on the result of a vectorized comparison to see if all or any of the comparisons are true, respectively. The results from these functions are sure to be length 1 so they are appropriate for use in if clauses, while the results from the vectorized comparis...
std::next_permutation Implementation Explanation
... Generation in lexicographic order. There are numbers of such algorithm in Combinatorics, but this is the most classical one.
– chain ro
Mar 10 '15 at 2:59
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Name of this month (Date.today.month as name)
I'm using Date.today.month to display the month number. Is there a command to get the month name, or do I need to make a case to get it?
...
What is the apply function in Scala?
...alk about "applying function f to its argument x".
In mathematics and computer science, Apply is a function that applies
functions to arguments.
Wikipedia
apply serves the purpose of closing the gap between Object-Oriented and Functional paradigms in Scala. Every function in Scala can be...