test(poly): Implemented data-driven testing for poly

tests/CMakeLists.txt

@@ -17,9 +17,7 @@ endmacro()
 
 add_test_executable(test_dist dist/test_dist.cpp)
 
-add_test_executable(test_lagrange poly/test_lagrange.cpp poly/test_case.h)
-add_test_executable(test_imp_lagrange poly/test_imp_lagrange.cpp poly/test_case.h)
-add_test_executable(test_newton poly/test_newton.cpp poly/test_case.h)
+add_test_executable(test_poly poly/test_poly.cpp)
 
 add_test_executable(test_barycentric misc/test_barycentric.cpp)
 

tests/poly/test_poly.cpp

@@ -0,0 +1,44 @@
+#include <ALFI/poly.h>
+
+#include "../test_utils.h"
+
+const auto test_data_path = TEST_DATA_DIR "/poly/poly.toml";
+
+const auto test_data = toml::parse_file(test_data_path);
+
+void test_polynomial(const auto& function_coeffs, const auto& function_vals,
+					 double epsilon_coeffs, double epsilon_values, double epsilon_vals) {
+	const auto& test_cases = test_data["test_cases"].ref<toml::array>();
+
+	test_cases.for_each([&](const toml::table& test_case) {
+		const auto& X = to_vector<double>(test_case["X"].ref<toml::array>());
+		const auto& Y = to_vector<double>(test_case["Y"].ref<toml::array>());
+		const auto& coeffs = to_vector<double>(test_case["coeffs"].ref<toml::array>());
+		const auto& xx = to_vector<double>(test_case["xx"].ref<toml::array>());
+		const auto& yy = to_vector<double>(test_case["yy"].ref<toml::array>());
+
+		const auto P = function_coeffs(X, Y);
+		expect_eq(P, coeffs, epsilon_coeffs);
+		const auto values = alfi::poly::val(P, xx);
+		expect_eq(values, yy, epsilon_values);
+		const auto vals = function_vals(X, Y, xx);
+		expect_eq(vals, yy, epsilon_vals);
+	});
+}
+
+// need this workaround because of the fourth parameter of `alfi::poly::imp_lagrange_vals`
+static const auto& imp_lagrange_vals = [](const auto& X, const auto& Y, const auto& xx) {
+	return alfi::poly::imp_lagrange_vals<>(X, Y, xx);
+};
+
+TEST(PolynomialsTest, Lagrange) {
+	test_polynomial(alfi::poly::lagrange<>, alfi::poly::lagrange_vals<>, 1e-7, 1e-1, 1e-11);
+}
+
+TEST(PolynomialsTest, ImprovedLagrange) {
+	test_polynomial(alfi::poly::imp_lagrange<>, imp_lagrange_vals, 1e-4, 1e-4, 1e-11);
+}
+
+TEST(PolynomialsTest, Newton) {
+	test_polynomial(alfi::poly::newton<>, alfi::poly::newton_vals<>, 1e-8, 1e-4, 1e-5);
+}