From e1fd5ce5fa6ba64fb415dbecb50c32e76b512164 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?L=C3=A9a=20Saviot?= <lea.saviot@numworks.com>
Date: Fri, 23 Aug 2019 11:04:31 +0200
Subject: [PATCH] [poincare/norm_cdf] Evaluation using NormalDistribution

---
 poincare/src/norm_cdf.cpp       | 15 +++++++++++++--
 poincare/test/approximation.cpp |  3 +++
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/poincare/src/norm_cdf.cpp b/poincare/src/norm_cdf.cpp
index d58c57c84..7e9d02884 100644
--- a/poincare/src/norm_cdf.cpp
+++ b/poincare/src/norm_cdf.cpp
@@ -1,5 +1,6 @@
 #include <poincare/norm_cdf.h>
 #include <poincare/layout_helper.h>
+#include <poincare/normal_distribution.h>
 #include <poincare/serialization_helper.h>
 #include <assert.h>
 
@@ -28,8 +29,18 @@ Expression NormCDFNode::shallowReduce(ReductionContext reductionContext) {
 
 template<typename T>
 Evaluation<T> NormCDFNode::templatedApproximate(Context * context, Preferences::ComplexFormat complexFormat, Preferences::AngleUnit angleUnit) const {
-  //TODO LEA
-  return Complex<T>::Builder(0.0);
+  Evaluation<T> aEvaluation = childAtIndex(0)->approximate(T(), context, complexFormat, angleUnit);
+  Evaluation<T> muEvaluation = childAtIndex(1)->approximate(T(), context, complexFormat, angleUnit);
+  Evaluation<T> sigmaEvaluation = childAtIndex(2)->approximate(T(), context, complexFormat, angleUnit);
+
+  T a = aEvaluation.toScalar();
+  T mu = muEvaluation.toScalar();
+  T sigma = sigmaEvaluation.toScalar();
+
+  if (std::isnan(a) || std::isnan(mu) || std::isnan(sigma)) {
+    return Complex<T>::Undefined();
+  }
+  return Complex<T>::Builder(NormalDistribution::CumulativeDistributiveFunctionAtAbscissa(a, mu, sigma));
 }
 
 Expression NormCDF::shallowReduce(ExpressionNode::ReductionContext reductionContext) {
diff --git a/poincare/test/approximation.cpp b/poincare/test/approximation.cpp
index 7e1f7f8b0..993b70295 100644
--- a/poincare/test/approximation.cpp
+++ b/poincare/test/approximation.cpp
@@ -276,6 +276,9 @@ QUIZ_CASE(poincare_approximation_function) {
   assert_expression_approximates_to<float>("log(2)", "0.30103");
   assert_expression_approximates_to<double>("log(2)", "3.0102999566398ᴇ-1");
 
+  assert_expression_approximates_to<float>("normcdf(1.2, 3.4, 5.6)", "0.3472125");
+  assert_expression_approximates_to<double>("normcdf(1.2, 3.4, 5.6)", "3.4721249841587ᴇ-1");
+
   assert_expression_approximates_to<float>("permute(10, 4)", "5040");
   assert_expression_approximates_to<double>("permute(10, 4)", "5040");