Resolve "Fix z_center cast in histo_utils.cxx"

Closes #64 (closed)

src/histo_utils.cxx

@@ -120,7 +120,8 @@ void print_histogram (const itk::Statistics::ImageToHistogramFilter<itk::VectorI
     idx4[1] = 1;
     idx4[2] = 1;
 
-    const HistogramType::AbsoluteFrequencyType z_center = histogram.GetMeasurementVector(idx1)[0];
+    const HistogramType::MeasurementVectorType measurement = histogram.GetMeasurementVector(idx1);
+    const VectorImageType::PixelType::ValueType z_center = measurement[0];
     const int Nz = histogram.GetFrequency(idx1) + histogram.GetFrequency(idx2) + histogram.GetFrequency(idx3) + histogram.GetFrequency(idx4);
     const int fcloud_z = histogram.GetFrequency(idx3) + histogram.GetFrequency(idx4);
     const int fsnow_z = histogram.GetFrequency(idx2) + histogram.GetFrequency(idx4);