do some trials

Today, I did some trials.

Summary:

I review all my codes and delete more outliers for outputs, but there is little improvement.

I compared the prediction results of predicting conductivity and permittivity separately and together. For the individual one, they are almost the same, so for now, it shows that whether to predict them separately or together will not affect the results' accuracy so much.

Also, because of the results shown yesterday, I recommend to choose depths as training and testing data randomly.

After discussing with Yifu, he tells me that f0=22MHz, f1=100MHz, f2=350MHz, f3=960MHz, which are from Hess.

Some trials may be done next week:
1. add 64 bin T2 distribution as inputs
2. see if delete some depths will improve the prediction result