diff --git a/lib/mathlib.cpp b/lib/mathlib.cpp
index 8fea77ba9..033ecfaa0 100644
--- a/lib/mathlib.cpp
+++ b/lib/mathlib.cpp
@@ -299,7 +299,9 @@ std::string MathLib::abs(const std::string &tok)
 
 bool MathLib::isEqual(const std::string &first, const std::string &second)
 {
-    return toDoubleNumber(first) == toDoubleNumber(second);
+    // this conversion is needed for formating
+    // e.g. if first=0.1 and second=1.0E-1, the direct comparison of the strings whould fail
+    return toString<double>(toDoubleNumber(first)) == toString<double>(toDoubleNumber(second));
 }
 
 bool MathLib::isNotEqual(const std::string &first, const std::string &second)
diff --git a/test/testmathlib.cpp b/test/testmathlib.cpp
index 65e7d2d96..f68b1c98c 100644
--- a/test/testmathlib.cpp
+++ b/test/testmathlib.cpp
@@ -44,7 +44,6 @@ private:
         TEST_CASE(isLessEqual)
     }
 
-
     void isGreater()
     {
         ASSERT_EQUALS(true , MathLib::isGreater("1.0", "0.001"));
@@ -63,6 +62,7 @@ private:
     {
         ASSERT_EQUALS(true  , MathLib::isEqual("1.0", "1.0"));
         ASSERT_EQUALS(false , MathLib::isEqual("1.", "1.01"));
+        ASSERT_EQUALS(true  , MathLib::isEqual("0.1","1.0E-1"));
     }
 
     void isNotEqual()