Function setupInputs

examples/benchmarks/cg.cpp:23–52

static array b;

void setupInputs() {
    // Generate a random input: A
    array T = randu(dimension, dimension, f32);
    // Create 0s in input.
    // Anything that is no divisible by sparsityFactor will become 0.
    A = floor(T * 1000);
    A = A * ((A % sparsityFactor) == 0) / 1000;
    // Make it positive definite
    A = transpose(A) + A + A.dims(0) * identity(A.dims(0), A.dims(0), f32);

    // Make A sparse as spA
    spA = sparse(A);

    // Generate x0: Random guess
    x0 = randu(A.dims(0), f32);

    // Generate b
    b = matmul(A, x0);

    std::cout << "Sparsity of A = "
              << 100.f * (float)sparseGetNNZ(spA) / (float)spA.elements() << "%"
              << std::endl;
    std::cout << "Memory Usage of A = " << A.bytes() / (1024.f * 1024.f)
              << " MB" << std::endl;
    std::cout << "Memory Usage of spA = "
              << (sparseGetValues(spA).bytes() + sparseGetRowIdx(spA).bytes() +
                  sparseGetColIdx(spA).bytes()) /
                     (1024.f * 1024.f)
              << " MB" << std::endl;
}

void sparseConjugateGradient(void) {
    array x = constant(0, b.dims(), f32);