From f4c9889b67fdaf3e7e77ceaeb2dde4a93445820a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?L=C3=A9a=20Saviot?= <lea.saviot@numworks.com>
Date: Tue, 27 Aug 2019 10:19:06 +0200
Subject: [PATCH] [apps/proba] Tests about binomial law

---
 apps/probability/Makefile               |  4 ++--
 apps/probability/test/distributions.cpp | 18 +++++++++++++++++-
 2 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/apps/probability/Makefile b/apps/probability/Makefile
index 860892894..57f946a83 100644
--- a/apps/probability/Makefile
+++ b/apps/probability/Makefile
@@ -2,6 +2,7 @@ apps += Probability::App
 app_headers += apps/probability/app.h
 
 app_probability_test_src = $(addprefix apps/probability/,\
+  distribution/binomial_distribution.cpp \
   distribution/chi_squared_distribution.cpp \
   distribution/geometric_distribution.cpp \
   distribution/helper.cpp \
@@ -9,6 +10,7 @@ app_probability_test_src = $(addprefix apps/probability/,\
   distribution/distribution.cpp \
   distribution/regularized_gamma.cpp \
   distribution/student_distribution.cpp \
+  distribution/two_parameter_distribution.cpp \
 )
 
 app_probability_src = $(addprefix apps/probability/,\
@@ -23,12 +25,10 @@ app_probability_src = $(addprefix apps/probability/,\
   calculation_type_controller.cpp \
   cell.cpp \
   image_cell.cpp \
-  distribution/binomial_distribution.cpp \
   distribution/exponential_distribution.cpp \
   distribution/normal_distribution.cpp \
   distribution/poisson_distribution.cpp \
   distribution/regularized_gamma.cpp \
-  distribution/two_parameter_distribution.cpp \
   distribution/uniform_distribution.cpp \
   distribution_controller.cpp \
   distribution_curve_view.cpp \
diff --git a/apps/probability/test/distributions.cpp b/apps/probability/test/distributions.cpp
index deab8b832..a1a46b13c 100644
--- a/apps/probability/test/distributions.cpp
+++ b/apps/probability/test/distributions.cpp
@@ -3,6 +3,7 @@
 #include <assert.h>
 #include <float.h>
 #include <cmath>
+#include "../distribution/binomial_distribution.h"
 #include "../distribution/chi_squared_distribution.h"
 #include "../distribution/geometric_distribution.h"
 #include "../distribution/student_distribution.h"
@@ -11,7 +12,7 @@ void assert_cumulative_distributive_function_direct_and_inverse_is(Probability::
   double r = distribution->cumulativeDistributiveFunctionAtAbscissa(x);
   quiz_assert(!std::isnan(r));
   quiz_assert(!std::isinf(r));
-  quiz_assert(std::abs(r-result)/result < FLT_EPSILON);
+  quiz_assert(std::abs(r-result) < FLT_EPSILON || std::abs(r-result)/result < FLT_EPSILON);
 
   r = distribution->cumulativeDistributiveInverseForProbability(&result);
   quiz_assert(!std::isnan(r));
@@ -22,6 +23,21 @@ void assert_cumulative_distributive_function_direct_and_inverse_is(Probability::
 
 //TODO other distributions
 
+QUIZ_CASE(binomial_distribution) {
+  // B(32, 0.6)
+  Probability::BinomialDistribution distribution;
+  distribution.setParameterAtIndex(32.0, 0);
+  distribution.setParameterAtIndex(0.6, 1);
+  assert_cumulative_distributive_function_direct_and_inverse_is(&distribution, 19.0, 0.53819340022502382137048471122398041188716888427734375);
+  assert_cumulative_distributive_function_direct_and_inverse_is(&distribution, 10.0, 0.00094770581410635293569122428181117356871254742145538330078125);
+
+  // B(17, 0.1)
+  distribution.setParameterAtIndex(17.0, 0);
+  distribution.setParameterAtIndex(0.1, 1);
+  assert_cumulative_distributive_function_direct_and_inverse_is(&distribution, 0.0, 0.166771816996665822596668249389040283858776092529296875);
+  assert_cumulative_distributive_function_direct_and_inverse_is(&distribution, 1.0, 0.4817852491014791294077213024138472974300384521484375);
+}
+
 QUIZ_CASE(chi_squared_distribution) {
   // Chi Squared distribution with 1 degree of freedom
   Probability::ChiSquaredDistribution distribution;