message: STYLE: use itk::Math::abs instead of fabs
diff: @@ -165,7 +165,7 @@ rtk::ThreeDCircularProjectionGeometry::AddProjection(const PointType & sourcePo
  const PointType & S = sourcePosition; // source pos
  const PointType & R = detectorPosition; // detector pos
  - if (fabs(r * c) > 1e-6) // non-orthogonal row/column vectors
  + if (itk::Math::abs(r * c) > 1e-6) // non-orthogonal row/column vectors
  return false;
  // Euler angles (ZXY convention) from detector orientation in IEC-based WCS:
  @@ -685,7 +685,7 @@ rtk::ThreeDCircularProjectionGeometry::VerifyAngles(const double outOfP
  for (int i = 0; i < 3; i++) // check whether matrices match
  for (int j = 0; j < 3; j++)
  - if (fabs(rm[i][j] - m[i][j]) > EPSILON)
  + if (itk::Math::abs(rm[i][j] - m[i][j]) > EPSILON)
  return false;
  return true;
  @@ -700,7 +700,7 @@ rtk::ThreeDCircularProjectionGeometry::FixAngles(double & outOfPlan
  const Matrix3x3Type & rm = referenceMatrix; // shortcut
  const double EPSILON = 1e-6; // internal tolerance for comparison
  - if (fabs(fabs(rm[2][1]) - 1.) > EPSILON)
  + if (itk::Math::abs(itk::Math::abs(rm[2][1]) - 1.) > EPSILON)
  {
  double oa = NAN, ga = NAN, ia = NAN;
  