Major Description
This bug is easy to reproduce, when use Multinomial Logistic Regression to train multiclass classification model with non-null initialWeights, it will throw an exception.
When you run
val lr = new LogisticRegressionWithLBFGS().setNumClasses(3)
val model = lr.run(input, initialWeights)
It will throw
requirement failed: LogisticRegressionModel.load with numClasses = 3 and numFeatures = -1 expected weights of length -2 (without intercept) or 0 (with intercept), but was given weights of length 10 java.lang.IllegalArgumentException: requirement failed: LogisticRegressionModel.load with numClasses = 3 and numFeatures = -1 expected weights of length -2 (without intercept) or 0 (with intercept), but was given weights of length 10
