Results for: "minmax"

Returns the object in enum that gives the maximum value from the given block.

If no block is given, an enumerator is returned instead.

a = %w(albatross dog horse)
a.max_by { |x| x.length }   #=> "albatross"

If the n argument is given, maximum n elements are returned as an array. These n elements are sorted by the value from the given block, in descending order.

a = %w[albatross dog horse]
a.max_by(2) {|x| x.length } #=> ["albatross", "horse"]

enum.max_by(n) can be used to implement weighted random sampling. Following example implements and use Enumerable#wsample.

module Enumerable
  # weighted random sampling.
  #
  # Pavlos S. Efraimidis, Paul G. Spirakis
  # Weighted random sampling with a reservoir
  # Information Processing Letters
  # Volume 97, Issue 5 (16 March 2006)
  def wsample(n)
    self.max_by(n) {|v| rand ** (1.0/yield(v)) }
  end
end
e = (-20..20).to_a*10000
a = e.wsample(20000) {|x|
  Math.exp(-(x/5.0)**2) # normal distribution
}
# a is 20000 samples from e.
p a.length #=> 20000
h = a.group_by {|x| x }
-10.upto(10) {|x| puts "*" * (h[x].length/30.0).to_i if h[x] }
#=> *
#   ***
#   ******
#   ***********
#   ******************
#   *****************************
#   *****************************************
#   ****************************************************
#   ***************************************************************
#   ********************************************************************
#   ***********************************************************************
#   ***********************************************************************
#   **************************************************************
#   ****************************************************
#   ***************************************
#   ***************************
#   ******************
#   ***********
#   *******
#   ***
#   *

Adds aProc as a finalizer, to be called after obj was destroyed. The object ID of the obj will be passed as an argument to aProc. If aProc is a lambda or method, make sure it can be called with a single argument.

Removes all finalizers for obj.

Adds a post-installs hook that will be passed a Gem::DependencyInstaller and a list of installed specifications when Gem::DependencyInstaller#install is complete

Returns true if the given instance variable is defined in obj. String arguments are converted to symbols.

class Fred
  def initialize(p1, p2)
    @a, @b = p1, p2
  end
end
fred = Fred.new('cat', 99)
fred.instance_variable_defined?(:@a)    #=> true
fred.instance_variable_defined?("@b")   #=> true
fred.instance_variable_defined?("@c")   #=> false

Defines a singleton method in the receiver. The method parameter can be a Proc, a Method or an UnboundMethod object. If a block is specified, it is used as the method body.

class A
  class << self
    def class_name
      to_s
    end
  end
end
A.define_singleton_method(:who_am_i) do
  "I am: #{class_name}"
end
A.who_am_i   # ==> "I am: A"

guy = "Bob"
guy.define_singleton_method(:hello) { "#{self}: Hello there!" }
guy.hello    #=>  "Bob: Hello there!"

DO NOT USE THIS DIRECTLY.

Hook method to return whether the obj can respond to id method or not.

When the method name parameter is given as a string, the string is converted to a symbol.

See respond_to?, and the example of BasicObject.

Invoked as a callback whenever a singleton method is undefined in the receiver.

module Chatty
  def Chatty.singleton_method_undefined(id)
    puts "Undefining #{id.id2name}"
  end
  def Chatty.one()   end
  class << self
     undef_method(:one)
  end
end

produces:

Undefining one

Checks for a method provided by this the delegate object by forwarding the call through _getobj_.

Convenience method for Shell::CommandProcessor.install_system_commands. Defines instance methods representing all the executable files found in Shell.default_system_path, with the given prefix prepended to their names.

Shell.install_system_commands
Shell.new.sys_echo("hello") # => hello

Specifies Emacs editing mode. The default is this mode. See the manual of GNU Readline for details of Emacs editing mode.

Raises NotImplementedError if the using readline library does not support.

Returns true if emacs mode is active. Returns false if not.

Raises NotImplementedError if the using readline library does not support.

Called when a map starts.

anchor is the anchor associated with the map or nil. tag is the tag associated with the map or nil. implicit is a boolean indicating whether or not the map was implicitly started. style is an integer indicating the mapping style.

See the constants in Psych::Nodes::Mapping for the possible values of style.

Example

Here is a YAML document that exercises most of the possible ways this method can be called:

---
k: !!map { hello: world }
v: &pewpew
  hello: world

The above YAML document consists of three maps, an outer map that contains two inner maps. Below is a matrix of the parameters sent in order to represent these three maps:

# anchor    tag                       implicit  style
[nil,       nil,                      true,     1     ]
[nil,       "tag:yaml.org,2002:map",  false,    2     ]
["pewpew",  nil,                      true,     1     ]

Called when a map ends

Start emitting a YAML map with anchor, tag, an implicit start and end, and style.

See Psych::Handler#start_mapping

Emit the end of a mapping.

See Psych::Handler#end_mapping

Returns the minor part of File_Stat#dev or nil.

File.stat("/dev/fd1").dev_minor   #=> 1
File.stat("/dev/tty").dev_minor   #=> 0

Returns the minor part of File_Stat#rdev or nil.

File.stat("/dev/fd1").rdev_minor   #=> 1
File.stat("/dev/tty").rdev_minor   #=> 0

Routes method calls to the referenced remote object.

The main loop performed by a DRbServer’s internal thread.

Accepts a connection from a client, and starts up its own thread to handle it. This thread loops, receiving requests from the client, invoking them on a local object, and returning responses, until the client closes the connection or a local method call fails.

Routes method calls to the referenced remote object.

Maximum number of times to retry an idempotent request in case of Net::ReadTimeout, IOError, EOFError, Errno::ECONNRESET, Errno::ECONNABORTED, Errno::EPIPE, OpenSSL::SSL::SSLError, Timeout::Error. Should be a non-negative integer number. Zero means no retries. The default value is 1.