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Factors in R: more than an annoyance?
One of the basic data types in R is factors. In my experience factors are basically a pain and I never use them. I always convert to characters. I feel oddly like I'm missing something.
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What is “assert” in JavaScript?
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There is no assert in JavaScript (yet; there's talk of adding one, but it's at an early stage). Perhaps you're using some library that provides one. The usual meaning is to throw an error if the expression passed into the function is false; this is part of the general concept of asserti...
How to normalize a NumPy array to within a certain range?
...ized within a range before it can be written back to a file. This can be done like so:
7 Answers
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Elastic search, multiple indexes vs one index and types for different data sets?
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number of shards can be customized per solution you select. You may have one index with 15 primary shards, or split it to 3 indexes for 5 shards - performance perspective won't change (assuming data are distributed equally)
think about data usage. Ie. if you use kibana to visualize, it's easier to...
What is the difference between a thread and a fiber?
.../etc.). This means that for threads, data integrity is a big issue because one thread may be stopped in the middle of updating a chunk of data, leaving the integrity of the data in a bad or incomplete state. This also means that the operating system can take advantage of multiple CPUs and CPU cores ...
How do I check if there are duplicates in a flat list?
For example, given the list ['one', 'two', 'one'] , the algorithm should return True , whereas given ['one', 'two', 'three'] it should return False .
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pull/push from multiple remote locations
...rge into HEAD, do:
git remote update
If it's not currently connected to one of the remotes, it will take time out or throw an error, and go on to the next. You'll have to manually merge from the fetched repositories, or cherry-pick, depending on how you want to organize collecting changes.
To fe...
What is an index in SQL?
...es are not unique. I might have a user database and want to query for everyone that lives in Gothenburg. An index on the "city" field would speed up my query. But there are more than 1 user living in Gothenburg so the index must be non-unique.
– Emil Vikström
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Library not loaded: /usr/local/opt/readline/lib/libreadline.6.2.dylib
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This one did it for me on El Capitan
– Sebastian Sastre
Oct 20 '16 at 13:18
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Why does C++ compilation take so long?
...reds or even thousands of headers to be (1) loaded and (2) compiled.
Every one of them typically has to be recompiled for every compilation unit,
because the preprocessor ensures that the result of compiling a header might vary between every compilation unit.
(A macro may be defined in one compilati...