linear Regression model in rusty_machine

lin_reg_model.rs

// MODEL! 
let mut linearRegression = LinRegressor::default(); 
// train 
linearRegression.train(&x_train_matrix, &y_train_vector);
// predictions
let preds = linearRegression.predict(&x_test_matrix).unwrap();
// convert to matrix both preds and y_test 
let preds_matrix = Matrix::new(test_size, 1, preds); 
let y_preds_matrix = Matrix::new(test_size, 1, y_test);
// compute the mse
let mse = neg_mean_squared_error(&preds_matrix, &y_preds_matrix); 

println!("Final negMSE (the higher the better) {:?}", mse);
// return the mse 
mse