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R memory management / cannot allocate vector of size n Mb
...m when you need to make objects of this size. Use gc() to clear now unused memory, or, better only create the object you need in one session.
If the above cannot help, get a 64-bit machine with as much RAM as you can afford, and install 64-bit R.
If you cannot do that there are many online servi...
Switching between GCC and Clang/LLVM using CMake
...between using GCC or Clang/LLVM to compile them. I believe (please correct me if I'm mistaken!) that to use Clang I need to set the following:
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How to access the last value in a vector?
Suppose I have a vector that is nested in a dataframe one or two levels. Is there a quick and dirty way to access the last value, without using the length() function? Something ala PERL's $# special var?
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How to efficiently count the number of keys/properties of an object in JavaScript?
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To do this in any ES5-compatible environment, such as Node, Chrome, IE 9+, Firefox 4+, or Safari 5+:
Object.keys(obj).length
Browser compatibility
Object.keys documentation (includes a method you can add to non-ES5 browsers)
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How do I show a MySQL warning that just happened?
I just ran a simple MySQL CREATE TABLE statement that produced the line
3 Answers
3
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Is That REST API Really RPC? Roy Fielding Seems to Think So
...ecessary because the information is a bit scattered. The actual question comes at the end if you're already familiar with this topic.
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How is Python's List Implemented?
...It's a dynamic array. Practical proof: Indexing takes (of course with extremely small differences (0.0013 µsecs!)) the same time regardless of index:
...>python -m timeit --setup="x = [None]*1000" "x[500]"
10000000 loops, best of 3: 0.0579 usec per loop
...>python -m timeit --setup="x = [No...
How to pass arguments into a Rake task with environment in Rails? [duplicate]
I am able to pass in arguments as follows:
5 Answers
5
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Sending command line arguments to npm script
... server.js --port=1337 => npm run server -- --port=1337
To get the parameter value, see this question. For reading named parameters, it's probably best to use a parsing library like yargs or minimist; nodejs exposes process.argv globally, containing command line parameter values, but this is a l...
pandas GroupBy columns with NaN (missing) values
I have a DataFrame with many missing values in columns which I wish to groupby:
9 Answers
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