STYLE: Address Greptile review on PrincipalComponentsAnalysis

itkVectorFieldPCA.h: in-class-initialize the GaussianDistanceKernel
members so Evaluate() before SetKernelSigma() is well-defined; drop
the unused m_VertexCount member that was never assigned.

itkVectorFieldPCA.hxx: drop the redundant inner if(m_PointSet) check
— control reaches it only after the preceding if(!m_PointSet) throw.
Remove the m_VertexCount line from PrintSelf().

itkVectorKernelPCATest.cxx: drop the duplicated vnl_vector.h include
and the unused debugOut std::ofstream.

Author: hjmjohnson

Modules/Numerics/PrincipalComponentsAnalysis/include/itkVectorFieldPCA.h

@@ -97,8 +97,8 @@ class ITK_TEMPLATE_EXPORT GaussianDistanceKernel : public KernelFunctionBase<TRe
   }
 
 private:
-  double m_KernelSigma;
-  double m_OneOverMinusTwoSigmaSqr;
+  double m_KernelSigma{ 1.0 };
+  double m_OneOverMinusTwoSigmaSqr{ -0.5 };
 };
 
 template <typename TVectorFieldElementType,
@@ -227,7 +227,6 @@ class ITK_TEMPLATE_EXPORT VectorFieldPCA : public Object
   unsigned int m_ComponentCount{ 0 };
   unsigned int m_SetSize{ 0 };
   unsigned int m_VectorDimCount{ 0 };
-  unsigned int m_VertexCount{ 0 };
   unsigned int m_PointDim{ 0 };
 
   MatrixType m_V0;

Modules/Numerics/PrincipalComponentsAnalysis/include/itkVectorFieldPCA.hxx

@@ -98,15 +98,11 @@ VectorFieldPCA<TVectorFieldElementType,
       return;
     }
 
-    //  PointSet only necessary for Kernel PCA, but check that it matches if set...
-    if (m_PointSet)
+    //  PointSet only necessary for Kernel PCA, check that it matches.
+    if (m_PointSet->GetNumberOfPoints() != m_VectorDimCount)
     {
-      if (m_PointSet->GetNumberOfPoints() != m_VectorDimCount)
-      {
-        itkExceptionMacro("Point Set count (" << m_PointSet->GetNumberOfPoints()
-                                              << ") does not match vector field count (" << m_VectorDimCount << ").");
-        return;
-      }
+      itkExceptionMacro("Point Set count (" << m_PointSet->GetNumberOfPoints()
+                                            << ") does not match vector field count (" << m_VectorDimCount << ").");
     }
   }
 
@@ -323,7 +319,6 @@ VectorFieldPCA<TVectorFieldElementType,
   os << indent << "ComponentCount: " << this->m_ComponentCount << std::endl;
   os << indent << "SetSize: " << this->m_SetSize << std::endl;
   os << indent << "VectorDimCount: " << this->m_VectorDimCount << std::endl;
-  os << indent << "VertexCount: " << this->m_VertexCount << std::endl;
   os << indent << "PointDim: " << this->m_PointDim << std::endl;
 
   os << indent << "V0 : " << this->m_V0 << std::endl;

Modules/Numerics/PrincipalComponentsAnalysis/test/itkVectorKernelPCATest.cxx

@@ -21,7 +21,6 @@
 #include "itkVectorFieldPCA.h"
 #include "itkTestingMacros.h"
 #include "vnl/vnl_vector.h"
-#include "vnl/vnl_vector.h"
 
 
 template <typename TPixel, typename TMesh, typename TVectorContainer>
@@ -192,9 +191,6 @@ itkVectorKernelPCATest(int argc, char * argv[])
   pcaCalc->SetKernelFunction(distKernel);
 
 
-  std::ofstream debugOut;
-  debugOut.precision(15);
-
   // Get the output and perform basic checks
   unsigned int computedNumberOfAverageVectorFieldCols = pcaCalc->GetAveVectorField().cols();