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Is SQL or even TSQL Turing Complete?
...gned to be true programming languages, so that's kinda cheating).
In this set of slides Andrew Gierth proves that with CTE and Windowing SQL is Turing Complete, by constructing a cyclic tag system, which has been proved to be Turing Complete. The CTE feature is the important part however -- it allo...
What does numpy.random.seed(0) do?
...numpy.random.rand(4)
array([ 0.55, 0.72, 0.6 , 0.54])
With the seed reset (every time), the same set of numbers will appear every time.
If the random seed is not reset, different numbers appear with every invocation:
>>> numpy.random.rand(4)
array([ 0.42, 0.65, 0.44, 0.89])
>&g...
Why is Scala's immutable Set not covariant in its type?
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Set is invariant in its type parameter because of the concept behind sets as functions. The following signatures should clarify things slightly:
trait Set[A] extends (A=>Boolean) {
def apply(e: A): Boolean
}
If Set w...
How do you plot bar charts in gnuplot?
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Simple bar graph:
set boxwidth 0.5
set style fill solid
plot "data.dat" using 1:3:xtic(2) with boxes
data.dat:
0 label 100
1 label2 450
2 "bar label" 75
If you want to style your bars differently, you can do something like:
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How can I add items to an empty set in python
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D = {} is a dictionary not set.
>>> d = {}
>>> type(d)
<type 'dict'>
Use D = set():
>>> d = set()
>>> type(d)
<type 'set'>
>>> d.update({1})
>>> d.add(2)
>>> d.update([3,3...
Set a persistent environment variable from cmd.exe
I have to set environment variables on different windows machines, but I don't want to be bothered changing them manually by getting on the properties screen of "My Computer"
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Using custom std::set comparator
I am trying to change the default order of the items in a set of integers to be lexicographic instead of numeric, and I can't get the following to compile with g++:
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Why can't I stop vim from wrapping my code?
I can't stop vim from wrapping my Python code. If I enter :set nowrap like a champ, but it still wraps.
9 Answers
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Get current value of a setting in Vim
Is there a simple way of finding out the current value of a specified Vim setting? If I want to know the current value of, say tabstop , I can run:
...
Why is '+' not understood by Python sets?
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Python sets don't have an implementation for the + operator.
You can use | for set union and & for set intersection.
Sets do implement - as set difference. You can also use ^ for symmetric set difference (i.e., it will return ...