Eigen：将 Matrix3d 旋转转换为四元数

Posted 2023-04-12

【中文标题】Eigen：将 Matrix3d 旋转转换为四元数

【英文标题】：Eigen: convert Matrix3d rotation to Quaternion

【发布时间】：2014-03-12 18:49:04

【问题描述】：

我正在尝试将 Matrix3d 旋转转换为 Quaternion<double>，但到目前为止我只遇到了奇怪的编译器错误。我使用的代码是：

Quaternion<double> getQuaternionFromRotationMatrix(const Matrix3d& mat)

    AngleAxisd aa; 
    aa = mat;
    Quaternion<double> q = aa;// conversion error

    return q;

以及编译器错误：

path/src/Utils.cpp: In function ‘Eigen::Quaternion<double> Utils::getQuaternionFromRotationMatrix(const Matrix3d&)’:
path/src/Utils.cpp:55:26: error: conversion from ‘Eigen::AngleAxisd aka Eigen::AngleAxis<double>’ to non-scalar type ‘Eigen::Quaternion<double>’ requested
In file included from /usr/local/include/eigen3/Eigen/Core:283:0,
                 from /usr/local/include/eigen3/Eigen/Dense:1,
                 from path/include/Utils.h:4,
                 from path/src/Utils.cpp:1:
/usr/local/include/eigen3/Eigen/src/Core/Assign.h: In member function ‘Derived& Eigen::DenseBase<Derived>::lazyAssign(const Eigen::DenseBase<OtherDerived>&) [with OtherDerived = Eigen::Matrix<double, 3, 1>, Derived = Eigen::Block<Eigen::Matrix<double, 4, 4>, 4, -0x00000000000000001, true, true>]’:
/usr/local/include/eigen3/Eigen/src/Core/Assign.h:534:123:   instantiated from ‘static Derived& Eigen::internal::assign_selector<Derived, OtherDerived, false, false>::run(Derived&, const OtherDerived&) [with Derived = Eigen::Block<Eigen::Matrix<double, 4, 4>, 4, -0x00000000000000001, true, true>, OtherDerived = Eigen::Matrix<double, 3, 1>]’
/usr/local/include/eigen3/Eigen/src/Core/Assign.h:574:89:   instantiated from ‘Derived& Eigen::MatrixBase<Derived>::operator=(const Eigen::DenseBase<OtherDerived>&) [with OtherDerived = Eigen::Matrix<double, 3, 1>, Derived = Eigen::Block<Eigen::Matrix<double, 4, 4>, 4, -0x00000000000000001, true, true>]’
path/src/Utils.cpp:34:20:   instantiated from here
/usr/local/include/eigen3/Eigen/src/Core/Assign.h:504:3: error: static assertion failed: "YOU_MIXED_MATRICES_OF_DIFFERENT_SIZES"

有人知道如何在两种表示之间进行转换吗？

【参考方案1】：

AngleAxis 或 Matrix 的构造函数是显式，这意味着您必须编写如下转换：

Matrix3f mat;
Quaternionf q(mat);

或

Quaternionf q;
q = mat;

AngleAxis 也一样。