diff --git a/doc/ReleaseNotes.md b/doc/ReleaseNotes.md
--- a/doc/ReleaseNotes.md
+++ b/doc/ReleaseNotes.md
@@ -1,5 +1,9 @@
 # Laura++ release notes
 
+2nd December 2020 Thomas Latham
+* Fix LauFormulaPar to follow change in behaviour of TFormula
+  - see https://phab.hepforge.org/T129
+
 27th November 2020 Dan Johnson
 * Allow slope of NR exponential model to vary negative - improves fit stability in low-statistics fits
   - see https://phab.hepforge.org/T128
@@ -13,7 +17,7 @@
   - See https://phab.hepforge.org/T93
 
 22nd May 2020 Thomas Latham
-* Fix uninitialised variable (related to rho-omega mixin) in LauIsobarDynamics
+* Fix uninitialised variable (related to rho-omega mixing) in LauIsobarDynamics
 
 12th December 2019 Thomas Latham & Daniel Johnson
 * Fix issue with generation of events for categories with small expected yield
@@ -24,6 +28,7 @@
 
 6th - 20th November 2019 Thomas Latham
 * Adopt CMake as the build system
+  - See https://phab.hepforge.org/T33
 
 ===
 ## Laura++ v3r5
diff --git a/inc/LauFormulaPar.hh b/inc/LauFormulaPar.hh
--- a/inc/LauFormulaPar.hh
+++ b/inc/LauFormulaPar.hh
@@ -166,9 +166,7 @@
 		//! Vector of LauParameters in the formula
 		std::vector<LauParameter*> paramVec_;
 
-		//! Array 
-		Double_t* dummy_;
-		//! Array 
+		//! Array to hold parameter values to pass to formula
 		Double_t* paramArray_;
 
 		//! Choice to use Gaussian constraint
diff --git a/src/LauFormulaPar.cc b/src/LauFormulaPar.cc
--- a/src/LauFormulaPar.cc
+++ b/src/LauFormulaPar.cc
@@ -46,8 +46,7 @@
 	name_(forName),
 	formula_(forName,formula),
 	paramVec_(params),
-	dummy_(0),
-	paramArray_(0),
+	paramArray_(nullptr),
 	gaussConstraint_(kFALSE),
 	constraintMean_(0.0),
 	constraintWidth_(0.0)
@@ -59,21 +58,17 @@
 		gSystem->Exit(EXIT_FAILURE);
 	}
 
-	if (formula_.GetNdim() != 1){
-		std::cerr<<"ERROR in LauFormulaPar::evaluate : Given formula of dimension: "<<formula_.GetNdim()<<" and not 1"<<std::endl;
+	if (formula_.GetNdim() != 0){
+		std::cerr<<"ERROR in LauFormulaPar::evaluate : Given formula of dimension: "<<formula_.GetNdim()<<" and not 0"<<std::endl;
 		gSystem->Exit(EXIT_FAILURE);
 	}
 
-	// Dummy array for TFormula
-	dummy_ = new Double_t[1];
-
 	// Array of input parameters
 	paramArray_ = new Double_t[nPars];
 }
 
 LauFormulaPar::~LauFormulaPar()
 {
-	delete[] dummy_;
 	delete[] paramArray_;
 }
 
@@ -81,8 +76,7 @@
 	name_(rhs.name_),
 	formula_(rhs.formula_),
 	paramVec_(rhs.paramVec_),
-	dummy_(0),
-	paramArray_(0),
+	paramArray_(nullptr),
 	gaussConstraint_(rhs.gaussConstraint_),
 	constraintMean_(rhs.constraintMean_),
 	constraintWidth_(rhs.constraintWidth_)
@@ -94,14 +88,11 @@
 		gSystem->Exit(EXIT_FAILURE);
 	}
 
-	if (formula_.GetNdim() != 1){
-		std::cerr<<"ERROR in LauFormulaPar::evaluate : Given formula of dimension: "<<formula_.GetNdim()<<" and not 1"<<std::endl;
+	if (formula_.GetNdim() != 0){
+		std::cerr<<"ERROR in LauFormulaPar::evaluate : Given formula of dimension: "<<formula_.GetNdim()<<" and not 0"<<std::endl;
 		gSystem->Exit(EXIT_FAILURE);
 	}
 
-	// Dummy array for TFormula
-	dummy_ = new Double_t[1];
-
 	// Array of input parameters
 	paramArray_ = new Double_t[nPars];
 }
@@ -121,8 +112,6 @@
 			paramArray_ = new Double_t[nNewPars];
 		}
 
-		// NB no need to recreate dummy_
-
 		gaussConstraint_ = rhs.gaussConstraint_;
 		constraintMean_ = rhs.constraintMean_;
 		constraintWidth_ = rhs.constraintWidth_;
@@ -139,7 +128,7 @@
 		paramArray_[i] = paramVec_[i]->value();
 	}
 
-	return formula_.EvalPar(dummy_,paramArray_);
+	return formula_.EvalPar(nullptr,paramArray_);
 }
 
 Double_t LauFormulaPar::unblindValue() const
@@ -151,7 +140,7 @@
 		paramArray_[i] = paramVec_[i]->unblindValue();
 	}
 
-	return formula_.EvalPar(dummy_,paramArray_);
+	return formula_.EvalPar(nullptr,paramArray_);
 }
 
 Double_t LauFormulaPar::genValue() const
@@ -163,7 +152,7 @@
 		paramArray_[i] = paramVec_[i]->genValue();
 	}
 
-	return formula_.EvalPar(dummy_,paramArray_);
+	return formula_.EvalPar(nullptr,paramArray_);
 }
 
 Double_t LauFormulaPar::initValue() const
@@ -175,7 +164,7 @@
 		paramArray_[i] = paramVec_[i]->initValue();
 	}
 
-	return formula_.EvalPar(dummy_,paramArray_);
+	return formula_.EvalPar(nullptr,paramArray_);
 }
 
 Bool_t LauFormulaPar::fixed() const