Simplify x/y = 0

fintarin · Jul 11, 2023 · 0234b87 · 0234b87
1 parent 0ec2c47
commit 0234b87
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Showing 4 changed files with 13 additions and 2 deletions.
diff --git a/src/fintamath/expressions/binary/CompExpression.cpp b/src/fintamath/expressions/binary/CompExpression.cpp
@@ -59,6 +59,7 @@ ArgumentPtr CompExpression::preSimplify() const {
 
 CompExpression::SimplifyFunctionsVector CompExpression::getFunctionsForPostSimplify() const {
   static const CompExpression::SimplifyFunctionsVector simplifyFunctions = {
+      &CompExpression::divSimplify,   //
       &CompExpression::coeffSimplify, //
   };
   return simplifyFunctions;
@@ -80,6 +81,14 @@ std::shared_ptr<IFunction> CompExpression::getOppositeFunction(const IFunction &
   return oppositeFunctions.at(function.toString());
 }
 
+ArgumentPtr CompExpression::divSimplify(const IFunction &func, const ArgumentPtr &lhs, const ArgumentPtr &rhs) {
+  if (const auto lhsExpr = cast<IExpression>(lhs); lhsExpr && is<Div>(lhsExpr->getFunction())) {
+    return makeExpr(func, lhsExpr->getChildren().front(), rhs);
+  }
+
+  return {};
+}
+
 ArgumentPtr CompExpression::coeffSimplify(const IFunction &func, const ArgumentPtr &lhs, const ArgumentPtr &rhs) {
   if (auto lhsExpr = cast<IExpression>(lhs)) {
     if (is<Neg>(lhsExpr->getFunction())) {

diff --git a/src/fintamath/expressions/binary/CompExpression.hpp b/src/fintamath/expressions/binary/CompExpression.hpp
@@ -30,6 +30,8 @@ class CompExpression : public IBinaryExpressionCRTP<CompExpression, true> {
   static std::shared_ptr<IFunction> getLogicOppositeFunction(const IFunction &function);
 
 private:
+  static ArgumentPtr divSimplify(const IFunction &func, const ArgumentPtr &lhs, const ArgumentPtr &rhs);
+
   static ArgumentPtr coeffSimplify(const IFunction &func, const ArgumentPtr &lhs, const ArgumentPtr &rhs);
 
   bool isSolution = false;

diff --git a/tests/src/FintamathTests.cpp b/tests/src/FintamathTests.cpp
@@ -57,7 +57,7 @@ TEST(FintamathTests, fintamathTests) {
   EXPECT_EQ(expr.toString(), "x^2 - x y + y^2 = 0");
 
   expr = eqv(x / x - y / y, x / y);
-  EXPECT_EQ(expr.toString(), "x/y = 0");
+  EXPECT_EQ(expr.toString(), "x = 0");
 
   expr = eqv(pow(x, 2) - 10, 39);
   EXPECT_EQ(solve(expr).toString(), "x = -7 | x = 7");

diff --git a/tests/src/expressions/ExpressionFunctionsTests.cpp b/tests/src/expressions/ExpressionFunctionsTests.cpp
@@ -266,7 +266,7 @@ TEST(ExpressionFunctionsTests, solveTest) {
   EXPECT_EQ(solve(Expression("x y = 0")).toString(), "x y = 0");
   EXPECT_EQ(solve(Expression("2 x^a = 0")).toString(), "x^a = 0");
   EXPECT_EQ(solve(Expression("x^b a = 0")).toString(), "a x^b = 0");
-  EXPECT_EQ(solve(Expression("x/y = 0")).toString(), "x/y = 0");
+  EXPECT_EQ(solve(Expression("x/y = 0")).toString(), "x = 0");
   EXPECT_EQ(solve(Expression("x^2 - 2*sin(2) = 0")).toString(), "x = -sqrt(2) sqrt(sin(2)) | x = sqrt(2) sqrt(sin(2))");
 
   EXPECT_EQ(solve(Expression("E >= Ey")).toString(), "E y - E <= 0");