19 lines
454 B
Factor
19 lines
454 B
Factor
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! Copyright (c) 2008 Reginald Keith Ford II.
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! See http://factorcode.org/license.txt for BSD license.
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USING: kernel math math.derivatives ;
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IN: math.newtons-method
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! Newton's method of approximating roots
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<PRIVATE
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: newton-step ( x function -- x2 )
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dupd [ call ] [ derivative ] 2bi / - ; inline
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: newton-precision ( -- n ) 13 ; inline
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PRIVATE>
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: newtons-method ( guess function -- x )
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newton-precision [ [ newton-step ] keep ] times drop ;
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