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%  computational verification of ill-condition for Problem 4.3a
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f = poly([1 1 1])
z = roots(f)
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%  calulate forward error
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norm([1;1;1] - z)
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%  construct a polynomial with the computed roots
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g = poly([z(1),z(2),z(3)])
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%  backward error
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norm(f-g)
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%  showing the condition number is at least 10^10
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