The Matrix
class represents a mathematical matrix. It provides methods for creating matrices, operating on them arithmetically and algebraically, and determining their mathematical properties such as trace, rank, inverse, determinant, or eigensystem.
Raised when attempting to convert special float values (in particular Infinity
or NaN
) to numerical classes which don’t support them.
Float::INFINITY.to_r #=> FloatDomainError: Infinity
Provides mathematical functions.
Example:
require "bigdecimal/math" include BigMath a = BigDecimal((PI(100)/2).to_s) puts sin(a,100) # => 0.99999999999999999999......e0
The Benchmark
module provides methods to measure and report the time used to execute Ruby code.
Measure the time to construct the string given by the expression "a"*1_000_000_000
:
require 'benchmark' puts Benchmark.measure { "a"*1_000_000_000 }
On my machine (OSX 10.8.3 on i5 1.7 GHz) this generates:
0.350000 0.400000 0.750000 ( 0.835234)
This report shows the user CPU time, system CPU time, the sum of the user and system CPU times, and the elapsed real time. The unit of time is seconds.
Do some experiments sequentially using the bm
method:
require 'benchmark' n = 5000000 Benchmark.bm do |x| x.report { for i in 1..n; a = "1"; end } x.report { n.times do ; a = "1"; end } x.report { 1.upto(n) do ; a = "1"; end } end
The result:
user system total real 1.010000 0.000000 1.010000 ( 1.014479) 1.000000 0.000000 1.000000 ( 0.998261) 0.980000 0.000000 0.980000 ( 0.981335)
Continuing the previous example, put a label in each report:
require 'benchmark' n = 5000000 Benchmark.bm(7) do |x| x.report("for:") { for i in 1..n; a = "1"; end } x.report("times:") { n.times do ; a = "1"; end } x.report("upto:") { 1.upto(n) do ; a = "1"; end } end
The result:
user system total real for: 1.010000 0.000000 1.010000 ( 1.015688) times: 1.000000 0.000000 1.000000 ( 1.003611) upto: 1.030000 0.000000 1.030000 ( 1.028098)
The times for some benchmarks depend on the order in which items are run. These differences are due to the cost of memory allocation and garbage collection. To avoid these discrepancies, the bmbm
method is provided. For example, to compare ways to sort an array of floats:
require 'benchmark' array = (1..1000000).map { rand } Benchmark.bmbm do |x| x.report("sort!") { array.dup.sort! } x.report("sort") { array.dup.sort } end
The result:
Rehearsal ----------------------------------------- sort! 1.490000 0.010000 1.500000 ( 1.490520) sort 1.460000 0.000000 1.460000 ( 1.463025) -------------------------------- total: 2.960000sec user system total real sort! 1.460000 0.000000 1.460000 ( 1.460465) sort 1.450000 0.010000 1.460000 ( 1.448327)
Report statistics of sequential experiments with unique labels, using the benchmark
method:
require 'benchmark' include Benchmark # we need the CAPTION and FORMAT constants n = 5000000 Benchmark.benchmark(CAPTION, 7, FORMAT, ">total:", ">avg:") do |x| tf = x.report("for:") { for i in 1..n; a = "1"; end } tt = x.report("times:") { n.times do ; a = "1"; end } tu = x.report("upto:") { 1.upto(n) do ; a = "1"; end } [tf+tt+tu, (tf+tt+tu)/3] end
The result:
user system total real for: 0.950000 0.000000 0.950000 ( 0.952039) times: 0.980000 0.000000 0.980000 ( 0.984938) upto: 0.950000 0.000000 0.950000 ( 0.946787) >total: 2.880000 0.000000 2.880000 ( 2.883764) >avg: 0.960000 0.000000 0.960000 ( 0.961255)
mkmf.rb is used by Ruby C extensions to generate a Makefile which will correctly compile and link the C extension to Ruby and a third-party library.
The Math
module contains module functions for basic trigonometric and transcendental functions. See class Float
for a list of constants that define Ruby’s floating point accuracy.
Domains and codomains are given only for real (not complex) numbers.
Generated when trying to lookup a gem to indicate that the gem was found, but that it isn’t usable on the current platform.
fetch and install read these and report them to the user to aid in figuring out why a gem couldn’t be installed.
Raised when a gem dependencies file specifies a ruby version that does not match the current version.
Individual switch class. Not important to the user.
Defined within Switch
are several Switch-derived classes: NoArgument
, RequiredArgument
, etc.
The command manager registers and installs all the individual sub-commands supported by the gem command.
Extra commands can be provided by writing a rubygems_plugin.rb file in an installed gem. You should register your command against the Gem::CommandManager
instance, like this:
# file rubygems_plugin.rb require 'rubygems/command_manager' Gem::CommandManager.instance.register_command :edit
You should put the implementation of your command in rubygems/commands.
# file rubygems/commands/edit_command.rb class Gem::Commands::EditCommand < Gem::Command # ... end
See Gem::Command
for instructions on writing gem commands.
An error that indicates we weren’t able to fetch some data from a source
Used to raise parsing and loading errors
RemoteFetcher
handles the details of fetching gems and gem information from a remote source.
SpecFetcher
handles metadata updates from remote gem repositories.
A fake Gem::RemoteFetcher
for use in tests or to avoid real live HTTP requests when testing code that uses RubyGems.
Example:
@fetcher = Gem::FakeFetcher.new @fetcher.data['http://gems.example.com/yaml'] = source_index.to_yaml Gem::RemoteFetcher.fetcher = @fetcher use nested array if multiple response is needed @fetcher.data['http://gems.example.com/sequence'] = [['Success', 200, 'OK'], ['Failed', 401, 'Unauthorized']] @fetcher.fetch_path('http://gems.example.com/sequence') # => ['Success', 200, 'OK'] @fetcher.fetch_path('http://gems.example.com/sequence') # => ['Failed', 401, 'Unauthorized'] # invoke RubyGems code paths = @fetcher.paths assert_equal 'http://gems.example.com/yaml', paths.shift assert paths.empty?, paths.join(', ')
See RubyGems’ tests for more examples of FakeFetcher
.