c++ - OpenCV Neural Network train one iteration at a time -

the way know train multilayer neural network in opencv is:

cvann_mlp network; .... network.train(input, output, mat(), mat(), params, flags); 

but not print out meaningful debug (e.g. iteration count, current error,...), program sit there until finishes training, troublesome if dataset in gigabytes, there's no way can see progress.

how train network 1 iteration @ time, or print out debug while training?

problem not solved, question solved. answer: it's impossible far current opencv versions concerned.