C++ 当转换特征矩阵类型时，错误：在‘；之前预期的主表达式；浮动’；

错误消息表示编译器不知道

pose.cast

是一个模板。对于类成员

.foo

可以是什么，有三个基本选项：

值（例如数据成员或

enum

值）

类型名称（例如，使用

typedef

定义的内容）

上面其中一个的模板

在您的例子中，

pose

属于

Eigen:：Matrix

类型。编译器还不知道

Eigen:：Matrix

是什么样子，因为它取决于

t

是什么（可能有人对不同类型的

Eigen:：Matrix

进行了专门化）

---

因此，当您访问未知类的成员时（如使用

pose.cast

），编译器会假定它的选项为#1（一个值）。这导致它解析

pose.cast@melpomene谢谢，出现了一个新错误，我将其更新为我的问题。您只发布了一半的错误消息。我后来发现Im使用的库之间存在冲突。
template <typename T>
      bool operator()(const T* parameters, T* residuals) const
    {
        Eigen::Matrix<T, 3, 1> pose(parameters[0],parameters[1],parameters[2]);
        Eigen::Vector3f pose1 = pose.cast<float>();
        Eigen::Affine2f transform = occ->getTransformForState(pose1);  // transform: rotation->translation


        Eigen::Vector3f tmp1 = occ->interpMapValueWithDerivatives(  transform * currPoint);

        Eigen::Matrix<T, 3, 1> transformedPointData(tmp1.cast<T>());  /// {M,dM/dx,dM/dy}

        T funVal = T(1) - transformedPointData[0];

        residuals[0] = funVal;

        return true;
    }

         Eigen::Vector3f pose1 = pose.cast<float>();

/usr/include/eigen3/Eigen/src/Core/MathFunctions.h: In instantiation of ‘static NewType Eigen::internal::cast_impl<OldType, NewType>::run(const OldType&) [with OldType = ceres::Jet<double, 3>; NewType = float]’:
/usr/include/eigen3/Eigen/src/Core/MathFunctions.h:328:44:   required from ‘NewType Eigen::internal::cast(const OldType&) [with OldType = ceres::Jet<double, 3>; NewType = float]’
/usr/include/eigen3/Eigen/src/Core/Functors.h:351:104:   required from ‘const NewType Eigen::internal::scalar_cast_op<Scalar, NewType>::operator()(const Scalar&) const [with Scalar = ceres::Jet<double, 3>; NewType = float]’
/usr/include/eigen3/Eigen/src/Core/CwiseUnaryOp.h:114:75:   required from ‘const Scalar Eigen::CwiseUnaryOpImpl<UnaryOp, XprType, Eigen::Dense>::coeff(Eigen::CwiseUnaryOpImpl<UnaryOp, XprType, Eigen::Dense>::Index) const [with UnaryOp = Eigen::internal::scalar_cast_op<ceres::Jet<double, 3>, float>; XprType = const Eigen::Matrix<ceres::Jet<double, 3>, 3, 1, 0, 3, 1>; Eigen::CwiseUnaryOpImpl<UnaryOp, XprType, Eigen::Dense>::Scalar = float; Eigen::CwiseUnaryOpImpl<UnaryOp, XprType, Eigen::Dense>::Index = long int]’
/usr/include/eigen3/Eigen/src/Core/DenseCoeffsBase.h:495:33:   required from ‘void Eigen::DenseCoeffsBase<Derived, 1>::copyCoeff(Eigen::DenseCoeffsBase<Derived, 1>::Index, const Eigen::DenseBase<OtherDerived>&) [with OtherDerived = Eigen::CwiseUnaryOp<Eigen::internal::scalar_cast_op<ceres::Jet<double, 3>, float>, const Eigen::Matrix<ceres::Jet<double, 3>, 3, 1, 0, 3, 1> >; Derived = Eigen::Matrix<float, 3, 1>; Eigen::DenseCoeffsBase<Derived, 1>::Index = long int]’
/usr/include/eigen3/Eigen/src/Core/Assign.h:180:5:   required from ‘static void Eigen::internal::assign_LinearTraversal_CompleteUnrolling<Derived1, Derived2, Index, Stop>::run(Derived1&, const Derived2&) [with Derived1 = Eigen::Matrix<float, 3, 1>; Derived2 = Eigen::CwiseUnaryOp<Eigen::internal::scalar_cast_op<ceres::Jet<double, 3>, float>, const Eigen::Matrix<ceres::Jet<double, 3>, 3, 1, 0, 3, 1> >; int Index = 0; int Stop = 3]’
/usr/include/eigen3/Eigen/src/Core/Assign.h:314:21:   [ skipping 5 instantiation contexts, use -ftemplate-backtrace-limit=0 to disable ]
/usr/include/eigen3/Eigen/src/Core/Matrix.h:281:31:   required from ‘Eigen::Matrix<_Scalar, _Rows, _Cols, _Options, _MaxRows, _MaxCols>::Matrix(const Eigen::MatrixBase<OtherDerived>&) [with OtherDerived = Eigen::CwiseUnaryOp<Eigen::internal::scalar_cast_op<ceres::Jet<double, 3>, float>, const Eigen::Matrix<ceres::Jet<double, 3>, 3, 1, 0, 3, 1> >; _Scalar = float; int _Rows = 3; int _Cols = 1; int _Options = 0; int _MaxRows = 3; int _MaxCols = 1]’

Eigen::Vector3f pose1 = pose.template cast<float>();