From 3911dc89b7e2de3bef3afa1464dfb3bf6863d72b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?L=C3=A9a=20Saviot?= <lea.saviot@numworks.com>
Date: Thu, 19 Sep 2019 10:48:12 +0200
Subject: [PATCH] [poincare/normcdf2] Fix shallowReduce (mu and var indexes
 were wrong)

---
 poincare/include/poincare/norm_cdf2.h                    | 2 ++
 poincare/include/poincare/normal_distribution_function.h | 7 +++++++
 poincare/src/normal_distribution_function.cpp            | 4 ++--
 poincare/test/simplification.cpp                         | 3 +++
 4 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/poincare/include/poincare/norm_cdf2.h b/poincare/include/poincare/norm_cdf2.h
index cb02dc4b0..08167c0bd 100644
--- a/poincare/include/poincare/norm_cdf2.h
+++ b/poincare/include/poincare/norm_cdf2.h
@@ -22,6 +22,8 @@ public:
   Type type() const override { return Type::NormCDF2; }
   Sign sign(Context * context) const override { return Sign::Positive; }
   Expression setSign(Sign s, ReductionContext reductionContext) override;
+  int muIndex() const override { return 2; }
+  int varIndex() const override { return 3; }
 
 private:
   // Layout
diff --git a/poincare/include/poincare/normal_distribution_function.h b/poincare/include/poincare/normal_distribution_function.h
index 746a29f5a..e2cb7b800 100644
--- a/poincare/include/poincare/normal_distribution_function.h
+++ b/poincare/include/poincare/normal_distribution_function.h
@@ -8,6 +8,9 @@ namespace Poincare {
 // NormalDistributionFunctions are NormCDF, NormCDF2, InvNorm and NormPDF
 
 class NormalDistributionFunctionNode : public ExpressionNode {
+public:
+  virtual int muIndex() const { return 1; }
+  virtual int varIndex() const { return 2; }
 private:
   // Simplication
   Expression shallowReduce(ReductionContext reductionContext) override;
@@ -19,6 +22,10 @@ class NormalDistributionFunction : public Expression {
 public:
   NormalDistributionFunction(const NormalDistributionFunctionNode * n) : Expression(n) {}
   Expression shallowReduce(Context * context, bool * stopReduction = nullptr);
+private:
+  int muIndex() const { return node()->muIndex(); }
+  int varIndex() const { return node()->varIndex(); }
+  NormalDistributionFunctionNode * node() const { return static_cast<NormalDistributionFunctionNode *>(Expression::node()); }
 };
 
 }
diff --git a/poincare/src/normal_distribution_function.cpp b/poincare/src/normal_distribution_function.cpp
index 53acdd596..e0bfb96e5 100644
--- a/poincare/src/normal_distribution_function.cpp
+++ b/poincare/src/normal_distribution_function.cpp
@@ -19,8 +19,8 @@ Expression NormalDistributionFunction::shallowReduce(Context * context, bool * s
     }
   }
 
-  Expression mu = childAtIndex(1);
-  Expression var = childAtIndex(2);
+  Expression mu = childAtIndex(muIndex());
+  Expression var = childAtIndex(varIndex());
 
   // Check mu and var
   bool muAndVarOK = false;
diff --git a/poincare/test/simplification.cpp b/poincare/test/simplification.cpp
index 3095a4a99..21ac81800 100644
--- a/poincare/test/simplification.cpp
+++ b/poincare/test/simplification.cpp
@@ -1082,4 +1082,7 @@ QUIZ_CASE(poincare_probability) {
   assert_parsed_expression_simplify_to("invnorm(3/4,2,random())", "invnorm(3/4,2,random())"); // random can be 0
   assert_parsed_expression_simplify_to("invnorm(0.5,2,0)", Undefined::Name());
   assert_parsed_expression_simplify_to("invnorm(0.5,2,-1)", Undefined::Name());
+  assert_parsed_expression_simplify_to("normcdf(2,0,1)", "normcdf(2,0,1)");
+  assert_parsed_expression_simplify_to("normcdf2(1,2,0,1)", "normcdf2(1,2,0,1)");
+  assert_parsed_expression_simplify_to("normpdf(2,0,1)", "normpdf(2,0,1)");
 }