[apps/reg] Add tests

apps/regression/Makefile

@@ -42,4 +42,36 @@ i18n_files += $(addprefix apps/regression/,\
   base.universal.i18n\
 )
 
+tests += $(addprefix apps/regression/test/,\
+  model.cpp\
+)
+test_objs += $(addprefix apps/regression/,\
+  regression_context.o\
+  store.o\
+)
+test_objs += $(addprefix apps/shared/,\
+  store_context.o\
+)
+test_objs += $(addprefix apps/shared/,\
+  curve_view_cursor.o\
+  curve_view_range.o\
+  double_pair_store.o\
+  interactive_curve_view_range.o\
+  interactive_curve_view_range_delegate.o\
+  memoized_curve_view_range.o\
+  store_context.o\
+)
+test_objs += $(addprefix apps/regression/model/,\
+  cubic_model.o\
+  exponential_model.o\
+  linear_model.o\
+  logarithmic_model.o\
+  logistic_model.o\
+  model.o\
+  power_model.o\
+  quadratic_model.o\
+  quartic_model.o\
+  trigonometric_model.o\
+)
+
 app_images += apps/regression/regression_icon.png

apps/regression/test/model.cpp

@@ -0,0 +1,95 @@
+#include <quiz.h>
+#include <string.h>
+#include <assert.h>
+#include "../model/model.h"
+#include "../regression_context.h"
+#include "../store.h"
+
+using namespace Poincare;
+using namespace Regression;
+
+/* The data was generated by choosing X1 and the coefficients of the regression,
+ * then filling Y1 with the regression formula + random()/10. */
+
+void assert_regression_is(double * xi, double * yi, int numberOfPoints, Model::Type modelType, double * trueCoefficients) {
+  double precision = 0.1;
+  int series = 0;
+  Regression::Store store;
+
+  // Set the points and the regression type
+  for (int i = 0; i < numberOfPoints; i++) {
+    store.set(xi[i], series, 0, i);
+    store.set(yi[i], series, 1, i);
+  }
+  RegressionContext context(&store);
+  store.setSeriesRegressionType(series, modelType);
+
+  // Compute the coefficients
+  double * coefficients = store.coefficientsForSeries(series, &context);
+
+  // Comapre the coefficients
+  int numberOfCoefs = store.modelForSeries(series)->numberOfCoefficients();
+  for (int i = 0; i < numberOfCoefs; i++) {
+    assert(std::fabs(coefficients[i] - trueCoefficients[i]) < precision);
+  }
+}
+
+QUIZ_CASE(linear_regression) {
+  double x[] = {1.0, 8.0, 14.0, 79.0};
+  double y[] = {-3.581, 20.296, 40.676, 261.623};
+  double coefficients[] = {3.4, -7.0};
+  assert_regression_is(x, y, 4, Model::Type::Linear, coefficients);
+}
+
+QUIZ_CASE(quadratic_regression) {
+  double x[] = {-34.0, -12.0, 5.0, 86.0, -2.0};
+  double y[] = {-8241.389, -1194.734, -59.163, - 46245.39, -71.774};
+  double coefficients[] = {-6.5, 21.3, -3.2};
+  assert_regression_is(x, y, 5, Model::Type::Quadratic, coefficients);
+}
+
+QUIZ_CASE(cubic_regression) {
+  double x[] = {-3.0, -2.8, -1.0, 0.0, 12.0};
+  double y[] = {691.261, 566.498, 20.203, -12.865, -34293.21};
+  double coefficients[] = {-21.2, 16.0, 4.1, -12.9};
+  assert_regression_is(x, y, 5, Model::Type::Cubic, coefficients);
+}
+
+QUIZ_CASE(quartic_regression) {
+  double x[] = {1.6, 3.5, 3.5, -2.8, 6.4, 5.3, 2.9, -4.8, -5.7, 3.1};
+  double y[] = {-112.667, -1479.824, -1479.805, 1140.276, -9365.505, -5308.355, -816.925, 5554.007, 9277.107, -1009.874};
+  double coefficients[] = {0.6, -43, 21.5, 3.1, -0.5};
+  assert_regression_is(x, y, 10, Model::Type::Quartic, coefficients);
+}
+
+QUIZ_CASE(logarithmic_regression) {
+  double x[] = {0.2, 0.5, 5, 7};
+  double y[] = {-11.952, -9.035, -1.695, -0.584};
+  double coefficients[] = {3.2, -6.9};
+  assert_regression_is(x, y, 4, Model::Type::Logarithmic, coefficients);
+}
+
+QUIZ_CASE(exponential_regression) {
+  double x[] = {5.5, 5.6, 5.7, 5.8, 5.9, 6.0};
+  double y[] = {-276.842, -299.956, -324.933, -352.0299, -381.314, -413.0775};
+  double coefficients[] = {-3.4, 0.8};
+  assert_regression_is(x, y, 6, Model::Type::Exponential, coefficients);
+}
+
+QUIZ_CASE(power_regression) {
+  double x[] = {1.0, 50.0, 34.0, 67.0, 20.0};
+  double y[] = {71.860, 2775514, 979755.1, 6116830, 233832.9};
+  double coefficients[] = {71.8, 2.7};
+  assert_regression_is(x, y, 5, Model::Type::Power, coefficients);
+}
+
+// No case for trigonometric regression, because it has no unique solution
+
+/* This data was generated without the random error, otherwise it did not pass
+ * the test. */
+QUIZ_CASE(logistic_regression) {
+  double x[] = {2.3, 5.6, 1.1, 4.3};
+  double y[] = {3.948, 4.694, 2.184, 4.656};
+  double coefficients[] = {6, 1.5, 4.7};
+  assert_regression_is(x, y, 4, Model::Type::Logistic, coefficients);
+}