linux-kernel-module-cheat/userland/libs/openblas/hello.c

/* https://cirosantilli.com/linux-kernel-module-cheat#blas
 * Adapted from: https://github.com/xianyi/OpenBLAS/wiki/User-Manual/59b62f98e7400270fb03ad1d85fba5b64ebbff2b#call-cblas-interface
 */

#include <assert.h>
#include <cblas.h>

#include <lkmc/math.h>

int main(void) {
    double A[6] = {
         1.0, 2.0,  1.0,
        -3.0, 4.0, -1.0
    };
    double B[6] = {
         1.0,  2.0,
         1.0, -3.0,
         4.0, -1.0
    };
    double C[9] = {
        0.5, 0.5, 0.5,
        0.5, 0.5, 0.5,
        0.5, 0.5, 0.5
    };
    cblas_dgemm(
        CblasColMajor, CblasNoTrans, CblasTrans,
        3, 3, 2, 1, A, 3, B, 3, 2, C, 3
    );
    assert(lkmc_vector_equal(
        9,
        C,
        (double[]) {
            11.0, -9.0,  5.0,
            -9.0, 21.0, -1.0,
             5.0, -1.0,  3.0
        },
        1e-6
    ));
}