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Boolean operators && and ||
...rter ones are vectorized, meaning they can return a vector, like this:
((-2:2) >= 0) & ((-2:2) <= 0)
# [1] FALSE FALSE TRUE FALSE FALSE
The longer form evaluates left to right examining only the first element of each vector, so the above gives
((-2:2) >= 0) && ((-2:2) <...
How do I extract a sub-hash from a hash?
...main the same:
h1 = {:a => :A, :b => :B, :c => :C, :d => :D}
h2 = h1.select {|key, value| [:b, :d, :e, :f].include?(key) } # => {:b=>:B, :d=>:D}
h1 = Hash[h1.to_a - h2.to_a] # => {:a=>:A, :c=>:C}
And if you want to patch that into the Hash class:
class Hash
def ...
How do I calculate percentiles with python/numpy?
...
294
You might be interested in the SciPy Stats package. It has the percentile function you're afte...
With bash, how can I pipe standard error into another process?
...
172
There is also process substitution. Which makes a process substitute for a file.
You can send s...
Compare two List objects for equality, ignoring order [duplicate]
... before comparing:
Enumerable.SequenceEqual(list1.OrderBy(t => t), list2.OrderBy(t => t))
Edit:
Here is a solution that performs a bit better (about ten times faster), and only requires IEquatable, not IComparable:
public static bool ScrambledEquals<T>(IEnumerable<T> list1, IE...
How to profile a bash shell script slow startup?
...
132
If you have GNU date (or another version that can output nanoseconds), do this at the beginning ...
Array slices in C#
...
201
Arrays are enumerable, so your foo already is an IEnumerable<byte> itself.
Simply use LI...
How to convert a scala.List to a java.util.List?
... first have to convert the Scala List into a mutable collection.
On Scala 2.7:
import scala.collection.jcl.Conversions.unconvertList
import scala.collection.jcl.ArrayList
unconvertList(new ArrayList ++ List(1,2,3))
From Scala 2.8 onwards:
import scala.collection.JavaConversions._
import scala.c...
Regular expressions in C: examples?
...
238
Regular expressions actually aren't part of ANSI C. It sounds like you might be talking about ...