Correctly implement the decision_function_shape parameter.

SC-SGS · Nov 7, 2023 · ac1ebee · ac1ebee
1 parent f7f56bf
commit ac1ebee
Showing 1 changed file with 14 additions and 6 deletions.
diff --git a/bindings/Python/sklearn.cpp b/bindings/Python/sklearn.cpp
@@ -43,6 +43,7 @@ struct svc {
 
     std::optional<real_type> epsilon{};
     std::optional<long long> max_iter{};
+    plssvm::classification_type classification{ plssvm::classification_type::oao };
 
     std::unique_ptr<plssvm::csvm> svm_{ plssvm::make_csvm() };
     std::unique_ptr<data_set_type> data_{};
@@ -51,7 +52,7 @@ struct svc {
 
 void parse_provided_params(svc &self, const py::kwargs &args) {
     // check keyword arguments
-    check_kwargs_for_correctness(args, { "C", "kernel", "degree", "gamma", "coef0", "shrinking", "probability", "tol", "cache_size", "class_weight", "verbose", "max_iter", "decision_function_shape", "break_ties", "random_state" });
+    check_kwargs_for_correctness(args, { "C", "kernel", "degree", "gamma", "coef0", "shrinking", "probability", "tol", "cache_size", "class_weight", "verbose", "max_iter", "decision_function_shape", "break_ties", "random_state", "classification" });
 
     if (args.contains("C")) {
         self.svm_->set_params(plssvm::cost = args["C"].cast<typename svc::real_type>());
@@ -101,7 +102,14 @@ void parse_provided_params(svc &self, const py::kwargs &args) {
         self.max_iter = args["max_iter"].cast<long long>();
     }
     if (args.contains("decision_function_shape")) {
-        throw py::attribute_error{ "The 'decision_function_shape' parameter for a call to the 'SVC' constructor is not implemented yet!" };
+        const std::string &dfs = args["decision_function_shape"].cast<std::string>();
+        if (dfs == "ovo") {
+            self.classification = plssvm::classification_type::oao;
+        } else if (dfs == "ovr") {
+            self.classification = plssvm::classification_type::oaa;
+        } else {
+            throw py::value_error{ fmt::format("decision_function_shape must be either 'ovr' or 'ovo', got {}.", dfs) };
+        }
     }
     if (args.contains("break_ties")) {
         throw py::attribute_error{ "The 'break_ties' parameter for a call to the 'SVC' constructor is not implemented yet!" };
@@ -115,20 +123,20 @@ void fit(svc &self) {
     // fit the model using potentially provided keyword arguments
     if (self.epsilon.has_value() && self.max_iter.has_value()) {
         self.model_ = std::make_unique<typename svc::model_type>(self.svm_->fit(*self.data_,
-                                                                                plssvm::classification = plssvm::classification_type::oao,
+                                                                                plssvm::classification = self.classification,
                                                                                 plssvm::epsilon = self.epsilon.value(),
                                                                                 plssvm::max_iter = self.max_iter.value()));
     } else if (self.epsilon.has_value()) {
         self.model_ = std::make_unique<typename svc::model_type>(self.svm_->fit(*self.data_,
-                                                                                plssvm::classification = plssvm::classification_type::oao,
+                                                                                plssvm::classification = self.classification,
                                                                                 plssvm::epsilon = self.epsilon.value()));
     } else if (self.max_iter.has_value()) {
         self.model_ = std::make_unique<typename svc::model_type>(self.svm_->fit(*self.data_,
-                                                                                plssvm::classification = plssvm::classification_type::oao,
+                                                                                plssvm::classification = self.classification,
                                                                                 plssvm::max_iter = self.max_iter.value()));
     } else {
         self.model_ = std::make_unique<typename svc::model_type>(self.svm_->fit(*self.data_,
-                                                                                plssvm::classification = plssvm::classification_type::oao));
+                                                                                plssvm::classification = self.classification));
     }
 }