reproduce cifar result about largemargin_softmax_loss

[xiaoboCASIA]

I also have the same problem on cifar10, the loss will explode after some (about 12000) iterations.

[wy1iu]

The prototxt actually works fine in my PC. In general, L-Softmax loss is indeed a little bit difficult to optimize since it defines a more difficult task than Softmax loss. However, the training prototxt file I provide is simply an example of how to use L-Softmax loss. If your network diverges, you should consider to change the parameters such as base, gamma, power, etc. to make lambda decrease more smoothly. There are more than one set of parameters that could achieve the performance in the paper. The last thing you can do if your network still diverges is to assign a small positive value to lambda_min, say 0.5. (it is a very rare case that you need to change lambda_min for CIFAR 10.) Also note that, you should use m=4 in L-Softmax loss if you want to reproduce the reported performance, while in the CIFAR10 example prototxt, m is set to 2. Thanks for these feedbacks.

[wy1iu]

BTW, I just fix a bug about lambda_min. You guys should use the new version.