Feature #10072 ยป implement_Vector.basis.patch
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* Vector
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* New methods:
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* Vector.basis Creates a standard basis +n+-vector.
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* Vector#@+ and Vector#@- .
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* Method
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| lib/matrix.rb | ||
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# To create a Vector:
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# * Vector.[](*array)
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# * Vector.elements(array, copy = true)
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# * Vector.basis(n, k)
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#
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# To access elements:
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# * #[](i)
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| ... | ... | |
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end
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#
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# Creates a standard basis +n+-vector.
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#
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def Vector.basis(n, k)
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raise ArgumentError, "invalid n (#{n} for 1..)" if n < 1
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raise ArgumentError, "invalid k (#{k} for 0..#{n - 1})" unless 0 <= k && k < n
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array = Array.new(n) {|i| i == k ? 1 : 0 }
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new convert_to_array(array, false)
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end
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#
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# Vector.new is private; use Vector[] or Vector.elements to create.
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#
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def initialize(array)
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| test/matrix/test_vector.rb | ||
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@w1 = Vector[2,3,4]
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end
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def test_basis
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assert_equal(Vector[1, 0, 0], Vector.basis(3, 0))
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assert_raise(ArgumentError) { Vector.basis(-1, 2) }
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assert_raise(ArgumentError) { Vector.basis(4, -1) }
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assert_raise(ArgumentError) { Vector.basis(3, 3) }
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end
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def test_identity
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assert_same @v1, @v1
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assert_not_same @v1, @v2
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