Numerical Methods, Binary, and finding two nearby machine numbers












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$begingroup$


I have the question,



Find the binary form of the number x = 2/7
Suppose that the number x = 2/7 is stored in a 32-bit computer.


Find the two nearby machine numbers $x−$ and $x+$. Which of the two machine numbers is taken to be the floating point representation, $fl(x)$, of $x$? What are the absolute and the relative roundoff errors in representing $x$ by $fl(x)$?



I know how to do the steps, the issue im having is when calculating the machine numbers, $x+$ and $x-$, to calculate $fl(x)$ my binary form is correct but I feel I am converting back incorrectly.



e.g for $x-(x-)$ the binary form is $(1.0010010010010...) ·2^{-26}$
I need to convert this into decimal/fractional form to compare with $(x+) - x$, which should be $mathbf{4/7 ·2^{-25}}$. It seems I can't get the answer.










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    0












    $begingroup$


    I have the question,



    Find the binary form of the number x = 2/7
    Suppose that the number x = 2/7 is stored in a 32-bit computer.


    Find the two nearby machine numbers $x−$ and $x+$. Which of the two machine numbers is taken to be the floating point representation, $fl(x)$, of $x$? What are the absolute and the relative roundoff errors in representing $x$ by $fl(x)$?



    I know how to do the steps, the issue im having is when calculating the machine numbers, $x+$ and $x-$, to calculate $fl(x)$ my binary form is correct but I feel I am converting back incorrectly.



    e.g for $x-(x-)$ the binary form is $(1.0010010010010...) ·2^{-26}$
    I need to convert this into decimal/fractional form to compare with $(x+) - x$, which should be $mathbf{4/7 ·2^{-25}}$. It seems I can't get the answer.










    share|cite|improve this question











    $endgroup$















      0












      0








      0





      $begingroup$


      I have the question,



      Find the binary form of the number x = 2/7
      Suppose that the number x = 2/7 is stored in a 32-bit computer.


      Find the two nearby machine numbers $x−$ and $x+$. Which of the two machine numbers is taken to be the floating point representation, $fl(x)$, of $x$? What are the absolute and the relative roundoff errors in representing $x$ by $fl(x)$?



      I know how to do the steps, the issue im having is when calculating the machine numbers, $x+$ and $x-$, to calculate $fl(x)$ my binary form is correct but I feel I am converting back incorrectly.



      e.g for $x-(x-)$ the binary form is $(1.0010010010010...) ·2^{-26}$
      I need to convert this into decimal/fractional form to compare with $(x+) - x$, which should be $mathbf{4/7 ·2^{-25}}$. It seems I can't get the answer.










      share|cite|improve this question











      $endgroup$




      I have the question,



      Find the binary form of the number x = 2/7
      Suppose that the number x = 2/7 is stored in a 32-bit computer.


      Find the two nearby machine numbers $x−$ and $x+$. Which of the two machine numbers is taken to be the floating point representation, $fl(x)$, of $x$? What are the absolute and the relative roundoff errors in representing $x$ by $fl(x)$?



      I know how to do the steps, the issue im having is when calculating the machine numbers, $x+$ and $x-$, to calculate $fl(x)$ my binary form is correct but I feel I am converting back incorrectly.



      e.g for $x-(x-)$ the binary form is $(1.0010010010010...) ·2^{-26}$
      I need to convert this into decimal/fractional form to compare with $(x+) - x$, which should be $mathbf{4/7 ·2^{-25}}$. It seems I can't get the answer.







      binary






      share|cite|improve this question















      share|cite|improve this question













      share|cite|improve this question




      share|cite|improve this question








      edited Jan 4 at 21:56









      Rafa Budría

      5,7151825




      5,7151825










      asked Jan 4 at 21:39









      Mitul SuchakMitul Suchak

      65




      65






















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