I've been using a bunch of scikit-learn Transformer classes to pipeline and combine features for point-wise ranking modeling and I'd like to convert these features into LibSVM format to experiment with XGBoost and other methods. Is there any easy way to dump scikit-learn features into LibSVM format? Thanks.
I believe you're looking for sklearn.datasets.dump_svmlight_file.
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I'm looking for a way to do the conversion, the only information I've found is how to go from Keras and other to CoreML.
You'll have to write your own code to do this, there is no automated conversion tool for Core ML models to Keras (only the other way around).
i want to know is there any method by which the computer can decide which classification model to use ( Decision trees, logistic regression, KNN, etc. ) by just looking at the training data.
even just the math will be extremely helpful.
I am going to be writing this in python 3, so if there's any built method in scikit-learn or tensorflow for this purpose,it would be of great help.
This scikit learn tool kit solves it :
https://automl.github.io/auto-sklearn/stable/index.html
Is the scikit learn implementation version of LibSVM nearly as computationally efficient as the original LibSVM?
Does anyone have any stats on the comparison?
Thanks!
There is no point in comparison. Sklearn's SVC is just a wrapper around libsvm. So up to data manipulation "around" it (pre- and post processing), it is exactly the same.
I want to extract features using caffe and train those features using SVM. I have gone through this link: http://caffe.berkeleyvision.org/gathered/examples/feature_extraction.html. This links provides how we can extract features using caffenet. But I want to use Lenet architecture here. I am unable to change this line of command for Lenet:
./build/tools/extract_features.bin models/bvlc_reference_caffenet/bvlc_reference_caffenet.caffemodel examples/_temp/imagenet_val.prototxt fc7 examples/_temp/features 10 leveldb
And also, after extracting the features, how to train these features using SVM? I want to use python for this. For eg: If I get features from this code:
features = net.blobs['pool2'].data.copy()
Then, how can I train these features using SVM by defining my own classes?
You have two questions here:
Extracting features using LeNet
Training an SVM
Extracting features using LeNet
To extract the features from LeNet using the extract_features.bin script you need to have the model file (.caffemodel) and the model definition for testing (.prototxt).
The signature of extract_features.bin is here:
Usage: extract_features pretrained_net_param feature_extraction_proto_file extract_feature_blob_name1[,name2,...] save_feature_dataset_name1[,name2,...] num_mini_batches db_type [CPU/GPU] [DEVICE_ID=0]
So if you take as an example val prototxt file this one (https://github.com/BVLC/caffe/blob/master/models/bvlc_alexnet/train_val.prototxt), you can change it to the LeNet architecture and point it to your LMDB / LevelDB. That should get you most of the way there. Once you did that and get stuck, you can re-update your question or post a comment here so we can help.
Training SVM on top of features
I highly recommend using Python's scikit-learn for training an SVM from the features. It is super easy to get started, including reading in features saved from Caffe's format.
Very lagged reply, but should help.
Not 100% what you want, but I have used the VGG-16 net to extract face features using caffe and perform a accuracy test on a small subset of the LFW dataset. Exactly what you needed is in the code. The code creates classes for training and testing and pushes them into the SVM for classification.
https://github.com/wajihullahbaig/VGGFaceMatching
I have trained a SVM (svc) using scikit-learn over half a terabyte of data. The model is working fine and I need to port it to C, but I don't want to re-train the SVM from scratch because it takes way too long for me. Is there a way to easily export the model generated by scikit-learn and import it into LibSVM? Internally scikit-learn uses LibSVM so theoretically it should be possible, but I haven't been able to find anything in the documentation. Any suggestion?
Is there a way to easily export the model generated by scikit-learn and import it into LibSVM?
No. The scikit-learn version of LIBSVM has been hacked up severely to fit it into the Python environment and the model is stored as NumPy/SciPy data structures.
Your best shot is to study the SVM decision function and reimplement it in C. The support vectors can be obtained from the SVC object as NumPy arrays, which are easily translated to C arrays.