From ec8b5d06257830ac277e3ea82dacd3761d6771ee Mon Sep 17 00:00:00 2001 From: marcandre Date: Sun, 2 May 2010 05:43:29 +0000 Subject: * NEWS: List all changes to lib/matrix * lib/matrix.rb: Improve doc and style. Trivial optimizations. git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@27585 b2dd03c8-39d4-4d8f-98ff-823fe69b080e --- lib/matrix.rb | 177 +++++++++++++++++++++++++++++----------------------------- 1 file changed, 90 insertions(+), 87 deletions(-) (limited to 'lib') diff --git a/lib/matrix.rb b/lib/matrix.rb index a3394246aa..ee26cb94d0 100644 --- a/lib/matrix.rb +++ b/lib/matrix.rb @@ -1,21 +1,15 @@ -#-- -# matrix.rb - -# $Release Version: 1.0$ -# $Revision: 1.13 $ -# Original Version from Smalltalk-80 version -# on July 23, 1985 at 8:37:17 am -# by Keiju ISHITSUKA -#++ +# encoding: utf-8 # # = matrix.rb # # An implementation of Matrix and Vector classes. # -# Author:: Keiju ISHITSUKA -# Documentation:: Gavin Sinclair (sourced from Ruby in a Nutshell (Matsumoto, O'Reilly)) -# # See classes Matrix and Vector for documentation. # +# Current Maintainer:: Marc-André Lafortune +# Original Author:: Keiju ISHITSUKA +# Original Documentation:: Gavin Sinclair (sourced from Ruby in a Nutshell (Matsumoto, O'Reilly)) +## require "e2mmap.rb" @@ -31,15 +25,9 @@ module ExceptionForMatrix # :nodoc: end # -# The +Matrix+ class represents a mathematical matrix, and provides methods for creating -# special-case matrices (zero, identity, diagonal, singular, vector), operating on them -# arithmetically and algebraically, and determining their mathematical properties (trace, rank, -# inverse, determinant). -# -# Note that matrices must be rectangular, otherwise an ErrDimensionMismatch is raised. -# -# Also note that the determinant of integer matrices may be approximated unless you -# also require 'mathn'. This may be fixed in the future. +# The +Matrix+ class represents a mathematical matrix. It provides methods for creating +# matrices, operating on them arithmetically and algebraically, +# and determining their mathematical properties (trace, rank, inverse, determinant). # # == Method Catalogue # @@ -115,9 +103,6 @@ end # * #inspect # class Matrix - @RCS_ID='-$Id: matrix.rb,v 1.13 2001/12/09 14:22:23 keiju Exp keiju $-' - -# extend Exception2MessageMapper include Enumerable include ExceptionForMatrix @@ -145,13 +130,13 @@ class Matrix # -1 66 # def Matrix.rows(rows, copy = true) - rows = Matrix.convert_to_array(rows) + rows = convert_to_array(rows) rows.map! do |row| - Matrix.convert_to_array(row, copy) + convert_to_array(row, copy) end size = (rows[0] || []).size rows.each do |row| - Matrix.Raise ErrDimensionMismatch, "element size differs (#{row.size} should be #{size})" unless row.size == size + Matrix.Raise ErrDimensionMismatch, "row size differs (#{row.size} should be #{size})" unless row.size == size end new rows, size end @@ -200,7 +185,7 @@ class Matrix def Matrix.diagonal(*values) size = values.size rows = (0 ... size).collect {|j| - row = Array.new(size).fill(0, 0, size) + row = Array.new(size, 0) row[j] = values[j] row } @@ -215,7 +200,7 @@ class Matrix # 0 5 # def Matrix.scalar(n, value) - Matrix.diagonal(*Array.new(n).fill(value, 0, n)) + Matrix.diagonal(*Array.new(n, value)) end # @@ -249,7 +234,7 @@ class Matrix # => 4 5 6 # def Matrix.row_vector(row) - row = Matrix.convert_to_array(row) + row = convert_to_array(row) new [row] end @@ -262,13 +247,13 @@ class Matrix # 6 # def Matrix.column_vector(column) - column = Matrix.convert_to_array(column) + column = convert_to_array(column) new [column].transpose, 1 end # # Creates a empty matrix of +row_size+ x +column_size+. - # +row_size+ or +column_size+ must be 0. + # At least one of +row_size+ or +column_size+ must be 0. # # m = Matrix.empty(2, 0) # m == Matrix[ [], [] ] @@ -417,7 +402,7 @@ class Matrix # # Returns a section of the matrix. The parameters are either: # * start_row, nrows, start_col, ncols; OR - # * col_range, row_range + # * row_range, col_range # # Matrix.diagonal(9, 5, -3).minor(0..1, 0..2) # => 9 0 0 @@ -430,17 +415,19 @@ class Matrix def minor(*param) case param.size when 2 - from_row = param[0].first + row_range, col_range = param + from_row = row_range.first from_row += row_size if from_row < 0 - to_row = param[0].end + to_row = row_range.end to_row += row_size if to_row < 0 - to_row += 1 unless param[0].exclude_end? + to_row += 1 unless row_range.exclude_end? size_row = to_row - from_row - from_col = param[1].first + + from_col = col_range.first from_col += column_size if from_col < 0 - to_col = param[1].end + to_col = col_range.end to_col += column_size if to_col < 0 - to_col += 1 unless param[1].exclude_end? + to_col += 1 unless col_range.exclude_end? size_col = to_col - from_col when 4 from_row, size_row, from_col, size_col = param @@ -521,7 +508,7 @@ class Matrix # There should be no good reason to do this since Matrices are immutable. # def clone - new_matrix @rows.map{|row| row.dup}, column_size + new_matrix @rows.map(&:dup), column_size end # @@ -654,21 +641,18 @@ class Matrix # def inverse Matrix.Raise ErrDimensionMismatch unless square? - Matrix.I(row_size).inverse_from(self) + Matrix.I(row_size).send(:inverse_from, self) end alias inv inverse - # - # Not for public consumption? - # - def inverse_from(src) - size = row_size + def inverse_from(src) # :nodoc: + last = row_size - 1 a = src.to_a - size.times do |k| + 0.upto(last) do |k| i = k akk = a[k][k].abs - (k+1 ... size).each do |j| + (k+1).upto(last) do |j| v = a[j][k].abs if v > akk i = j @@ -682,39 +666,40 @@ class Matrix end akk = a[k][k] - size.times do |ii| + 0.upto(last) do |ii| next if ii == k q = a[ii][k].quo(akk) a[ii][k] = 0 - (k + 1 ... size).each do |j| + (k + 1).upto(last) do |j| a[ii][j] -= a[k][j] * q end - size.times do |j| + 0.upto(last) do |j| @rows[ii][j] -= @rows[k][j] * q end end - (k + 1 ... size).each do |j| + (k+1).upto(last) do |j| a[k][j] = a[k][j].quo(akk) end - size.times do |j| + 0.upto(last) do |j| @rows[k][j] = @rows[k][j].quo(akk) end end self end - #alias reciprocal inverse + private :inverse_from # - # Matrix exponentiation. Defined for integer powers only. Equivalent to - # multiplying the matrix by itself N times. + # Matrix exponentiation. Currently implemented for integer powers only. + # Equivalent to multiplying the matrix by itself N times. # Matrix[[7,6], [3,9]] ** 2 # => 67 96 # 48 99 # def ** (other) - if other.kind_of?(Integer) + case other + when Integer x = self if other <= 0 x = self.inverse @@ -727,7 +712,7 @@ class Matrix return z if (other >>= 1).zero? x *= x end - elsif other.kind_of?(Float) || defined?(Rational) && other.kind_of?(Rational) + when Float, Rational Matrix.Raise ErrOperationNotImplemented, "**", self.class, other.class else Matrix.Raise ErrOperationNotDefined, "**", self.class, other.class @@ -796,8 +781,8 @@ class Matrix # It has the same computational cost order O(n^3) as standard Gaussian elimination. # Intermediate results are fraction free and of lower complexity. # A matrix of Integers will have thus intermediate results that are also Integers, - # with smaller bignums (if any), while a matrix of Float will usually have more - # precise intermediate results. + # with smaller bignums (if any), while a matrix of Float will usually have + # intermediate results with better precision. # def determinant_bareiss size = row_size @@ -973,7 +958,11 @@ class Matrix #++ # - # FIXME: describe #coerce. + # The coerce method provides support for Ruby type coercion. + # This coercion mechanism is used by Ruby to handle mixed-type + # numeric operations: it is intended to find a compatible common + # type between the two operands of the operator. + # See also Numeric#coerce. # def coerce(other) case other @@ -1010,17 +999,17 @@ class Matrix end def elements_to_f - warn "#{caller(1)[0]}: warning: Matrix#elements_to_f is deprecated" + warn "#{caller(1)[0]}: warning: Matrix#elements_to_f is deprecated, use map(&:to_f)" map(&:to_f) end def elements_to_i - warn "#{caller(1)[0]}: warning: Matrix#elements_to_i is deprecated" + warn "#{caller(1)[0]}: warning: Matrix#elements_to_i is deprecated, use map(&:to_i)" map(&:to_i) end def elements_to_r - warn "#{caller(1)[0]}: warning: Matrix#elements_to_r is deprecated" + warn "#{caller(1)[0]}: warning: Matrix#elements_to_r is deprecated, use map(&:to_r)" map(&:to_r) end @@ -1052,30 +1041,39 @@ class Matrix end end - # - # Converts the obj to an Array. If copy is set to true - # a copy of obj will be made if necessary. - # - def Matrix.convert_to_array(obj, copy = false) - case obj - when Array - copy ? obj.dup : obj - when Vector - obj.to_a - else - begin - converted = obj.to_ary - rescue Exception => e - raise TypeError, "can't convert #{obj.class} into an Array (#{e.message})" + # Private helper modules + + module ConversionHelper # :nodoc: + # + # Converts the obj to an Array. If copy is set to true + # a copy of obj will be made if necessary. + # + def convert_to_array(obj, copy = false) # :nodoc: + case obj + when Array + copy ? obj.dup : obj + when Vector + obj.to_a + else + begin + converted = obj.to_ary + rescue Exception => e + raise TypeError, "can't convert #{obj.class} into an Array (#{e.message})" + end + raise TypeError, "#{obj.class}#to_ary should return an Array" unless converted.is_a? Array + converted end - raise TypeError, "#{obj.class}#to_ary should return an Array" unless converted.is_a? Array - converted end + private :convert_to_array end - # Private helper module + extend ConversionHelper module CoercionHelper # :nodoc: + # + # Applies the operator +oper+ with argument +obj+ + # through coercion of +obj+ + # def apply_through_coercion(obj, oper) coercion = obj.coerce(self) raise TypeError unless coercion.is_a?(Array) && coercion.length == 2 @@ -1085,10 +1083,12 @@ class Matrix end private :apply_through_coercion + # # Helper method to coerce a value into a specific class. # Raises a TypeError if the coercion fails or the returned value # is not of the right class. # (from Rubinius) + # def self.coerce_to(obj, cls, meth) # :nodoc: return obj if obj.kind_of?(cls) @@ -1227,17 +1227,19 @@ class Vector include ExceptionForMatrix include Enumerable include Matrix::CoercionHelper + extend Matrix::ConversionHelper #INSTANCE CREATION private_class_method :new attr_reader :elements protected :elements + # # Creates a Vector from a list of elements. # Vector[7, 4, ...] # def Vector.[](*array) - new Matrix.convert_to_array(array, copy = false) + new convert_to_array(array, copy = false) end # @@ -1245,7 +1247,7 @@ class Vector # whether the array itself or a copy is used internally. # def Vector.elements(array, copy = true) - new Matrix.convert_to_array(array, copy) + new convert_to_array(array, copy) end # @@ -1502,7 +1504,11 @@ class Vector end # - # FIXME: describe Vector#coerce. + # The coerce method provides support for Ruby type coercion. + # This coercion mechanism is used by Ruby to handle mixed-type + # numeric operations: it is intended to find a compatible common + # type between the two operands of the operator. + # See also Numeric#coerce. # def coerce(other) case other @@ -1531,6 +1537,3 @@ class Vector str = "Vector"+@elements.inspect end end - -# Documentation comments: -# - Matrix#coerce and Vector#coerce need to be documented -- cgit v1.2.3