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[Lapack] Question on dsysv

Hi

 Great thanks for the windows edition of lapack. I successful compiled
lapack on my computer. While I failed to solve the function AX=B with
dsysv_(). I get the same B as output, which means the function is
unsolvable. While it should not be, I validate this with matlab.



Best wishes.



#include <iostream>

#include <stdio.h>

#include <array>

#include <vector>





extern "C" void dsysv_(const char *uplo, const int *N, const int *nrhs,
double *A,const int *lda,int* ipi , double *b,const int *ldb,double
*work,const int *lwork,int *info);





int main(void)

{



         char uplo = 'U';

         int n = 6;

         int nrhs = 1;

         int lDA = 6;

         int ipiv[6];

         int lDB = 6;

         double worksize;

         int lwork = -1;

         int info;

         double LHS[36]={ 1  ,   2  ,  3  ,   4  ,   5  ,   6,

                              2  ,   4   ,  6  ,   8 ,   10   , 12,

                              3  ,   6  ,   9  ,  12  ,  15 ,   18,

                              4   ,  8 ,   12,    16  ,  20 ,   24,

                              5 ,   10 ,   15 ,   20,    25 ,   30,

                              6 ,   12  ,  18 ,   24 ,   30 ,   36};



         double RHS[6]={ 154,308,462,616,770,900};

    dsysv_(&uplo, &n, &nrhs, LHS, &lDA, ipiv, RHS, &lDB, &worksize, &lwork,
&info);

         std::vector<double> work((int)worksize);

         lwork = (int)worksize;

         dsysv_(&uplo, &n, &nrhs, LHS, &lDA, ipiv, RHS, &lDB, work.data(),
&lwork, &info);



         for(int i=0;i<6;i++)

                   std::cout<< RHS[i]<<std::endl;

         std::cout<<info<<std::endl;



}
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