If x* is a local optimum of a function in all directions, could it be optimal in a neighborhood of x*?












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In a Euclidean space whose base is denoted $(e_1,e_2,...e_N)$. suppose that $x*$ is the local minimum of a function $f$ in all direction. Could we say that $x*$ is an optimum of $f$ in a neighborhood of $x*$ ??










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    In a Euclidean space whose base is denoted $(e_1,e_2,...e_N)$. suppose that $x*$ is the local minimum of a function $f$ in all direction. Could we say that $x*$ is an optimum of $f$ in a neighborhood of $x*$ ??










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      In a Euclidean space whose base is denoted $(e_1,e_2,...e_N)$. suppose that $x*$ is the local minimum of a function $f$ in all direction. Could we say that $x*$ is an optimum of $f$ in a neighborhood of $x*$ ??










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      In a Euclidean space whose base is denoted $(e_1,e_2,...e_N)$. suppose that $x*$ is the local minimum of a function $f$ in all direction. Could we say that $x*$ is an optimum of $f$ in a neighborhood of $x*$ ??







      optimization nonlinear-optimization






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      edited Nov 24 '18 at 2:35









      Moo

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      asked Nov 23 '18 at 20:05









      yas areyas are

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          Thats what a local minimum means. f has a local extremum at x$^*$ if for some $epsilon$-neighborhood of x$^*$, f(x) $ge$ f(x$^*$) for all x in the neighborhood.






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          • $begingroup$
            The question is: if f has a local minimum in "all ei directions" could it have a local minimum in a neighberhood of x*?
            $endgroup$
            – yas are
            Nov 23 '18 at 20:52











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          $begingroup$

          Thats what a local minimum means. f has a local extremum at x$^*$ if for some $epsilon$-neighborhood of x$^*$, f(x) $ge$ f(x$^*$) for all x in the neighborhood.






          share|cite|improve this answer









          $endgroup$













          • $begingroup$
            The question is: if f has a local minimum in "all ei directions" could it have a local minimum in a neighberhood of x*?
            $endgroup$
            – yas are
            Nov 23 '18 at 20:52
















          0












          $begingroup$

          Thats what a local minimum means. f has a local extremum at x$^*$ if for some $epsilon$-neighborhood of x$^*$, f(x) $ge$ f(x$^*$) for all x in the neighborhood.






          share|cite|improve this answer









          $endgroup$













          • $begingroup$
            The question is: if f has a local minimum in "all ei directions" could it have a local minimum in a neighberhood of x*?
            $endgroup$
            – yas are
            Nov 23 '18 at 20:52














          0












          0








          0





          $begingroup$

          Thats what a local minimum means. f has a local extremum at x$^*$ if for some $epsilon$-neighborhood of x$^*$, f(x) $ge$ f(x$^*$) for all x in the neighborhood.






          share|cite|improve this answer









          $endgroup$



          Thats what a local minimum means. f has a local extremum at x$^*$ if for some $epsilon$-neighborhood of x$^*$, f(x) $ge$ f(x$^*$) for all x in the neighborhood.







          share|cite|improve this answer












          share|cite|improve this answer



          share|cite|improve this answer










          answered Nov 23 '18 at 20:14









          Joel PereiraJoel Pereira

          68819




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          • $begingroup$
            The question is: if f has a local minimum in "all ei directions" could it have a local minimum in a neighberhood of x*?
            $endgroup$
            – yas are
            Nov 23 '18 at 20:52


















          • $begingroup$
            The question is: if f has a local minimum in "all ei directions" could it have a local minimum in a neighberhood of x*?
            $endgroup$
            – yas are
            Nov 23 '18 at 20:52
















          $begingroup$
          The question is: if f has a local minimum in "all ei directions" could it have a local minimum in a neighberhood of x*?
          $endgroup$
          – yas are
          Nov 23 '18 at 20:52




          $begingroup$
          The question is: if f has a local minimum in "all ei directions" could it have a local minimum in a neighberhood of x*?
          $endgroup$
          – yas are
          Nov 23 '18 at 20:52


















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