Using acceleration (CLAPACK) to solve the extended matrix?

Question

Does anyone know which function / method to use in Accelerate (CLAPACK) to solve an extended matrix like the one below? Look for some sample code, links to samples, tips on how to solve the matrix. I looked through the documentation, but most of them are related to more complex graphics systems, and there are hundreds of similar methods.

____ ____ | | | 4 3 -1 | 2 | | -2 3 8 | 0 | | 0 2 6 | -1 | |____ ____| 

Answer 1

 #include <Accelerate/Accelerate.h> #include <stdio.h> int main(int argc, char *argv[]) { /* Dimension of the matrix */ __CLPK_integer n = 3; /* Number of right-hand side vectors to solve for */ __CLPK_integer nrhs = 1; /* Note the ordering of the entries in A. LAPACK uses "column major" ordering as follows: 0 3 6 1 4 7 2 5 8 This is a Fortran-ism that persists in CLAPACK. */ double A[9] = {4.0, -2.0, 0.0, 3.0, 3.0, 2.0, -1.0, 8.0, 6.0 }; /* "Leading dimension" of the matrix; most of the time, this is just the matrix dimension (but not always; you'll learn about this by the time you need to use it. */ __CLPK_integer lda = 3; /* Integer array to hold information about the matrix factorization */ __CLPK_integer ipiv[3]; /* Right hand side to solve for */ double x[3] = { 2.0, 0.0, -1.0 }; /* Leading dimension of the right hand side vector */ __CLPK_integer ldb = 3; /* Status variable */ __CLPK_integer info; /* Solve the augmented system with a call to dgesv_. Note that this routine will overwrite the contents of the array A with a factored form of the matrix. If you need the original matrix, you need to copy it before calling dgesv_. Note that all the scalar arguments are passed as pointers; this too is a Fortran-ism. */ dgesv_(&n, &nrhs, A, &lda, ipiv, x, &ldb, &info); /* Handle error conditions */ if (info) printf("Could not solve system; dgesv exited with error %d\n", info); /* If no error, print the result */ else printf("Solution is [%f, %f, %f]\n", x[0], x[1], x[2]); return 0; } 

Compile and run:

  scanon$ gcc solve.c -framework Accelerate scanon$ ./a.out Solution is [-0.479167, 1.125000, -0.541667]