pub unsafe extern "C" fn d_mat_approx_equal(
mat1: *const d_mat_struct,
mat2: *const d_mat_struct,
eps: f64,
) -> c_intpub unsafe extern "C" fn d_mat_approx_equal(
mat1: *const d_mat_struct,
mat2: *const d_mat_struct,
eps: f64,
) -> c_int