add fit test helper methods, re #13349

Code/Mantid/Framework/CurveFitting/test/FitTestHelpers.h

+#ifndef FITTESTHELPERS_H_
+#define FITTESTHELPERS_H_
+
+#include "MantidAPI/AlgorithmManager.h"
+
+namespace FitTestHelpers {
+
+enum CurveBenchmarks { SingleB2BPeak, SmoothishGaussians };
+
+// forward-declare all helper functions
+static API::MatrixWorkspace_sptr generateCurveDataForFit(CurveBenchmarks ctype);
+
+static std::string generateFunctionDescrForFit(CurveBenchmarks ctype);
+
+static API::MatrixWorkspace_sptr generatePeaksCurveWorkspace();
+
+static API::MatrixWorkspace_sptr generateSmoothCurveWorkspace();
+
+static Mantid::API::IAlgorithm_sptr
+runFitAlgorithm(MatrixWorkspace_sptr dataToFit, CurveBenchmarks ctype,
+                const std::string minimizer = "Levenberg-MarquardtMD") {
+
+  auto fit = AlgorithmManager::Instance().create("Fit");
+  fit->initialize();
+
+  fit->setProperty("Minimizer", minimizer);
+  auto funcDescr = generateFunctionDescrForFit(ctype);
+  fit->setProperty("Function", funcDescr);
+  fit->setProperty("InputWorkspace", dataToFit);
+  fit->setProperty("CreateOutput", true);
+
+  fit->execute();
+
+  return fit;
+}
+
+/// Produces a workspace with data ready to be Fit-ted with the type of function
+/// passed
+static API::MatrixWorkspace_sptr
+generateCurveDataForFit(CurveBenchmarks ctype) {
+
+  if (SingleB2BPeak == ctype)
+    return generatePeaksCurveWorkspace();
+  else if (SmoothishGaussians == ctype)
+    return generateSmoothCurveWorkspace();
+  else
+    throw std::invalid_argument(
+        "Unknown curve type when trying to generate curve data: " + ctype);
+}
+
+/// Produces a string description of a function with parameters and values, as
+/// you can edit in the Fit browser
+static std::string generateFunctionDescrForFit(CurveBenchmarks ctype) {
+
+  if (SingleB2BPeak == ctype)
+    return "name=BackToBackExponential, X0=8500, S=800";
+  else if (SmoothishGaussians == ctype)
+    return "name=BSpline, Order=20, StartX=0, EndX=10";
+  else
+    throw std::invalid_argument("Unknown curve type when trying to generate a "
+                                "function description string: " +
+                                ctype);
+}
+
+// Equivalent python script. Create data with a peak and a bit of noise:
+// pws = CreateSampleWorkspace(Function="User Defined",
+// UserDefinedFunction="name=BackToBackExponential, I=15000, A=1, B=1.2,
+// X0=10000, S=400", NumBanks=1, BankPixelWidth=1, Random=True)
+static API::MatrixWorkspace_sptr generatePeaksCurveWorkspace() {
+
+  Mantid::API::IAlgorithm_sptr sampleAlg =
+      Mantid::API::AlgorithmManager::Instance().create("CreateSampleWorkspace");
+  sampleAlg->initialize();
+  sampleAlg->setChild(true);
+  sampleAlg->setProperty("Function", "User Defined");
+  sampleAlg->setProperty(
+      "UserDefinedFunction",
+      "name=BackToBackExponential, I=15000, A=1, B=1.2, X0=10000, S=400");
+  sampleAlg->setProperty("NumBanks", 1);
+  sampleAlg->setProperty("BankPixelWidth", 1);
+  sampleAlg->setProperty("XMin", 0.0);
+  sampleAlg->setProperty("XMax", 100.0);
+  sampleAlg->setProperty("BinWidth", 0.1);
+  sampleAlg->setProperty("Random", true);
+  sampleAlg->setPropertyValue("OutputWorkspace", "sample_peak_curve_ws");
+
+  sampleAlg->execute();
+  API::MatrixWorkspace_sptr ws = sampleAlg->getProperty("OutputWorkspace");
+
+  return ws;
+}
+
+// Equivalent python script. Create smooth-ish data curve:
+// ws = CreateSampleWorkspace(Function="User Defined",
+// UserDefinedFunction="name=LinearBackground, A0=0.4, A1=0.4; name=Gaussian,
+// PeakCentre=1.3, Height=7, Sigma=1.7; name=Gaussian, PeakCentre=5,
+// Height=10, Sigma=0.7; name=Gaussian, PeakCentre=8, Height=9, Sigma=1.8",
+// NumBanks=1, BankPixelWidth=1, XMin=0, XMax=10, BinWidth=0.01, Random=True)
+static API::MatrixWorkspace_sptr generateSmoothCurveWorkspace() {
+
+  Mantid::API::IAlgorithm_sptr sampleAlg =
+      Mantid::API::AlgorithmManager::Instance().create("CreateSampleWorkspace");
+  sampleAlg->initialize();
+  sampleAlg->setChild(true);
+  sampleAlg->setProperty("Function", "User Defined");
+  sampleAlg->setProperty(
+      "UserDefinedFunction",
+      "name=LinearBackground, A0=0.4, A1=0.4; name=Gaussian, PeakCentre=1.3, "
+      "Height=7, Sigma=1.7; name=Gaussian, PeakCentre=5, Height=10, "
+      "Sigma=0.7; name=Gaussian, PeakCentre=8, Height=9, Sigma=1.8");
+  sampleAlg->setProperty("NumBanks", 1);
+  sampleAlg->setProperty("BankPixelWidth", 1);
+  sampleAlg->setProperty("XMin", 0.0);
+  sampleAlg->setProperty("XMax", 10.0);
+  sampleAlg->setProperty("BinWidth", 0.01);
+  sampleAlg->setProperty("Random", true);
+  sampleAlg->setPropertyValue("OutputWorkspace", "sample_smooth_curve_ws");
+
+  sampleAlg->execute();
+  API::MatrixWorkspace_sptr ws = sampleAlg->getProperty("OutputWorkspace");
+
+  return ws;
+}
+}
+
+#endif /* FITTESTHELPERS_H_ */