From 65066596e8ec041cf2a558f737d3f055525e03b9 Mon Sep 17 00:00:00 2001
From: Andreas Suter <andreas.suter@psi.ch>
Date: Sat, 20 Apr 2024 09:40:04 +0200
Subject: [PATCH] improved bracket handling in function string generation.

---
 src/classes/PFunction.cpp | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/src/classes/PFunction.cpp b/src/classes/PFunction.cpp
index ef8bd0d2..712988a4 100644
--- a/src/classes/PFunction.cpp
+++ b/src/classes/PFunction.cpp
@@ -597,6 +597,7 @@ void PFunction::EvalTreeForString(tree_parse_info<> info)
 void PFunction::EvalTreeForStringExpression(iter_t const& i)
 {
   static Int_t termOp = 0;
+  static bool funcFlag = false;
 
   if (i->value.id() == PFunctionGrammar::realID) {
     assert(i->children.size() == 0);
@@ -627,7 +628,8 @@ void PFunction::EvalTreeForStringExpression(iter_t const& i)
     assert(i->children.size() == 0);
     fFuncString += boost::algorithm::trim_copy(std::string(i->value.begin(), i->value.end())).c_str();
   } else if (i->value.id() == PFunctionGrammar::functionID) {
-    assert(i->children.size() == 3);
+    assert(i->children.size() == 3);    
+    funcFlag = true;
     fFuncString += std::string(i->value.begin(), i->value.end()).c_str(); // keep function name
     fFuncString += "(";
     // '(', expression, ')'
@@ -635,6 +637,7 @@ void PFunction::EvalTreeForStringExpression(iter_t const& i)
     fFuncString += ")";
   } else if (i->value.id() == PFunctionGrammar::powerID) {
     assert(i->children.size() == 5);
+    funcFlag = true;
     fFuncString += std::string(i->value.begin(), i->value.end()).c_str(); // keep function name
     fFuncString += "(";
     // '(', expression, ',' expression, ')'
@@ -655,15 +658,21 @@ void PFunction::EvalTreeForStringExpression(iter_t const& i)
       assert(i->children.size() == 2);
       EvalTreeForStringExpression(i->children.begin());
       fFuncString += " / ";
-      fFuncString += "(";
+      if (((i->children.begin()+1)->children.size()>1) &&
+          ((i->children.begin()+1)->value.id() != PFunctionGrammar::functionID) &&
+           (i->children.begin()+1)->value.id() != PFunctionGrammar::powerID) // check if denominator is non-trivial and not a function
+        fFuncString += "(";
       EvalTreeForStringExpression(i->children.begin()+1);
-      fFuncString += ")";
+      if (((i->children.begin()+1)->children.size()>1)  &&
+          ((i->children.begin()+1)->value.id() != PFunctionGrammar::functionID) &&
+           (i->children.begin()+1)->value.id() != PFunctionGrammar::powerID) // check if denominator is non-trivial and not a function
+        fFuncString += ")";
     } else {
       assert(0);
     }
     termOp--;
   } else if (i->value.id() == PFunctionGrammar::expressionID) {
-    if (termOp > 0)
+    if ((termOp > 0) && !funcFlag)
       fFuncString += "(";
     if (*i->value.begin() == '+') {
       assert(i->children.size() == 2);
@@ -678,8 +687,9 @@ void PFunction::EvalTreeForStringExpression(iter_t const& i)
     } else {
       assert(0);
     }
-    if (termOp > 0)
+    if ((termOp > 0) && !funcFlag)
       fFuncString += ")";
+    funcFlag = false;
   } else if (i->value.id() == PFunctionGrammar::assignmentID) {
     assert(i->children.size() == 3);
     EvalTreeForStringExpression(i->children.begin());