Wait for GPU calculation to complete
wait(gpudev)
wait(gpudev) blocks execution
in MATLAB® until the GPU device identified by the GPUDevice object gpudev completes
its calculations. This can be used before calls to toc when timing GPU code that does not
gather results back to the workspace. When gathering results from
a GPU, MATLAB automatically waits until all GPU calculations
are complete, so you do not need to explicitly call wait in
that situation.