svd_compare using cuda and eigen to do svd GPU (stable) Cost's Time: 0.244256ms A: 0.011473, B: 0.014871, C: 0.999824, D: 0.579941 CPU (num upper, more slow) Cost's Time: 0.092256ms A: -0.011473, B: -0.014871, C: -0.999824, D: -0.579941