Question about roots of unity in the Fast Fourier Transform The Next CEO of Stack...

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Question about roots of unity in the Fast Fourier Transform



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I am learning about the Fast Fourier Transform, which converts a polynomial from its coefficient representation into its point-wise form using divide-and-conquer. The Fast Fourier Transform evaluates a polynomial of degree 'n' at 'n' distinct points. The 'n' distinct points are the 'nth' roots of unity.



I know that a root of unity is a complex number that when raised to some positive integer power 'n' is equal to 1. However, I am not sure what is the advantage of using roots of unity in the Fast Fourier Transform. Any insights are appreciated.










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    1












    $begingroup$


    I am learning about the Fast Fourier Transform, which converts a polynomial from its coefficient representation into its point-wise form using divide-and-conquer. The Fast Fourier Transform evaluates a polynomial of degree 'n' at 'n' distinct points. The 'n' distinct points are the 'nth' roots of unity.



    I know that a root of unity is a complex number that when raised to some positive integer power 'n' is equal to 1. However, I am not sure what is the advantage of using roots of unity in the Fast Fourier Transform. Any insights are appreciated.










    share|cite|improve this question









    $endgroup$















      1












      1








      1





      $begingroup$


      I am learning about the Fast Fourier Transform, which converts a polynomial from its coefficient representation into its point-wise form using divide-and-conquer. The Fast Fourier Transform evaluates a polynomial of degree 'n' at 'n' distinct points. The 'n' distinct points are the 'nth' roots of unity.



      I know that a root of unity is a complex number that when raised to some positive integer power 'n' is equal to 1. However, I am not sure what is the advantage of using roots of unity in the Fast Fourier Transform. Any insights are appreciated.










      share|cite|improve this question









      $endgroup$




      I am learning about the Fast Fourier Transform, which converts a polynomial from its coefficient representation into its point-wise form using divide-and-conquer. The Fast Fourier Transform evaluates a polynomial of degree 'n' at 'n' distinct points. The 'n' distinct points are the 'nth' roots of unity.



      I know that a root of unity is a complex number that when raised to some positive integer power 'n' is equal to 1. However, I am not sure what is the advantage of using roots of unity in the Fast Fourier Transform. Any insights are appreciated.







      fourier-analysis roots-of-unity fast-fourier-transform






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      share|cite|improve this question











      share|cite|improve this question




      share|cite|improve this question










      asked Mar 17 at 7:19









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