Sameer,

I have submitted the issue on
https://github.com/ceres-solver/ceres-solver/issues.

Oleg


On Sun, Jun 28, 2020 at 3:59 PM Sameer Agarwal <[email protected]>
wrote:

> Tobias,
>
> I have looked into this and added some details to the issue. As I
> understand it, these matrix algorithms require instantiating
> std::complex<ceres::Jet<T, N>, that leads to problems in the STL.
>
> Sameer
>
>
>
> On Thu, Jun 18, 2020 at 9:35 AM Sameer Agarwal <[email protected]>
> wrote:
>
>> sorry folks I have been missing in action, I will take a look as soon as
>> I can.
>> Sameer
>>
>>
>> On Sat, Jun 6, 2020 at 12:26 PM Wood, Tobias <[email protected]>
>> wrote:
>>
>>> Hello,
>>>
>>>
>>>
>>> I have opened an issue here:
>>> https://gitlab.com/libeigen/eigen/-/issues/1912
>>>
>>>
>>>
>>> I remembered that I did previously discuss the .exp() issue with Sameer
>>> on the Ceres mailing list, I have added a link to that, however I am now
>>> getting a slightly different error message because it looks like the
>>> internals of the STL have changed. Also, I have changed my algorithm
>>> slightly and now only need .pow(), but this does not work with Jets either.
>>> I think the problem with .pow() looks easier to fix?
>>>
>>>
>>>
>>> Thanks,
>>>
>>> Toby
>>>
>>>
>>>
>>> *From: *Rasmus Munk Larsen <[email protected]>
>>> *Reply to: *"[email protected]" <[email protected]>
>>> *Date: *Thursday, 4 June 2020 at 18:46
>>> *To: *eigen <[email protected]>, Sameer Agarwal <
>>> [email protected]>
>>> *Subject: *Re: [eigen] Using Eigen decompositions with ceres autodiff
>>> Jet data type.
>>>
>>>
>>>
>>> Hi Tobias,
>>>
>>> Please do. Sameer, since this is Ceres solver related, could I ask you
>>> to help out with this issue.
>>>
>>> Rasmus
>>>
>>>
>>>
>>> On Thu, Jun 4, 2020 at 3:06 AM Wood, Tobias <[email protected]>
>>> wrote:
>>>
>>> Hello,
>>>
>>>
>>>
>>> Apologies to bring up a tangentially related topic - Eigen's matrix
>>> exponential also doesn't work with Ceres Jets. There is some code inside
>>> the matrix exponential that checks if the scalar type is "known" to Eigen,
>>> I assume because there are some constants it requires. Jet<double> is not
>>> one of those types, so Eigen refuses to compile. When I encountered this
>>> problem earlier this year I worked around it by using Ceres numeric
>>> differentiation, but obviously if there's a chance to fix this and use
>>> auto-differentiation I would be very happy (big speed increase hopefully).
>>> Should I create an issue on the Eigen gitlab?
>>>
>>>
>>>
>>> Thanks,
>>>
>>> Toby
>>>
>>>
>>>
>>> *From: *Oleg Shirokobrod <[email protected]>
>>> *Reply to: *"[email protected]" <[email protected]>
>>> *Date: *Thursday, 4 June 2020 at 06:36
>>> *To: *"[email protected]" <[email protected]>
>>> *Subject: *Re: [eigen] Using Eigen decompositions with ceres autodiff
>>> Jet data type.
>>>
>>>
>>>
>>> 1. I would like to have autodiff ability, so I cannot use double for
>>> both A and b. If I cast b: A.jacobiSVD().solve( b.cast<T>()) everything
>>> works fine, but BinOp(T,T) is more expensive than BinOp(T, double). I would
>>> like to keep b as a vector of doubles.
>>>
>>> 2. T=Jet is ceres solver autodiff implementation type. There is a trait
>>> definition for Jet binary operations for type deduction such that
>>> type(Jet*double) = Jet and so on. It works when I do direct multiplication 
>>> VS^-1U^T
>>> * b. It works similar to complex scalar matrices and double rhs and there
>>> is the same problem for complex scalar cases.
>>>
>>> 3. I think that the mixed type deduction rule should give the same type
>>> for VS^-1U^T * b and  for A.jcobianSVD().solve(b); where A = USV^T because
>>> both use the same algorithm.
>>>
>>> 4. Unless there are serious reasons, deduction rules should be similar
>>> to scalar type equations. complex<double> A; double b; x = A^-1 * b;
>>> type(x) = complex<double>.
>>>
>>>
>>>
>>> On Wed, Jun 3, 2020 at 11:16 PM Rasmus Munk Larsen <[email protected]>
>>> wrote:
>>>
>>> Try to compile your code in debug mode with the type assertions on.
>>>
>>>
>>>
>>> On Wed, Jun 3, 2020 at 1:14 PM Rasmus Munk Larsen <[email protected]>
>>> wrote:
>>>
>>> Are you saying that you compute the decomposition in one type and solve
>>> with a RHS of a different type? Why do you say that VS^-1U^T * b should be
>>> Matrix<T>? That makes an assumption about type coercion rules. In fact, you
>>> cannot generally mix types in Eigen expressions without explicit casting,
>>> and U.adjoint() * b should fail if the types are different.
>>>
>>>
>>>
>>> On Wed, Jun 3, 2020 at 11:33 AM Oleg Shirokobrod <
>>> [email protected]> wrote:
>>>
>>> Rasmuss, I do not quite understand this issue. Decomposition solve
>>> should propagate scalar type of a matrix but not scalar type of its
>>> argument. Example:
>>>
>>> template <typename T> Matrix<T> A;
>>>
>>> VectorXd b;
>>>
>>> A.jcobiSVD().solve(b) should be of type Matrix<T> but it is not. Type of
>>> result is Matrix<double>. If we make SVD decomposition of A = USV^T and
>>> express result as VS^-1U^T * b, than result will be of type Matrix<T>.
>>> Which is correct and differs from result of solve which uses the same
>>> algorithm but more complex result’s type deduction. This is the problem.
>>>
>>>
>>>
>>> On Wed 3. Jun 2020 at 20.19, Rasmus Munk Larsen <[email protected]>
>>> wrote:
>>>
>>> OK, I opened https://gitlab.com/libeigen/eigen/-/issues/1909
>>> <https://eur03.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgitlab.com%2Flibeigen%2Feigen%2F-%2Fissues%2F1909&data=01%7C01%7Ctobias.wood%40kcl.ac.uk%7C9b7731b3d2c24c6ea7e908d808af4522%7C8370cf1416f34c16b83c724071654356%7C0&sdata=4adEoOhABpJiEJlKW29VCAHkhG4EXH6ZnSeSQr8dmJ0%3D&reserved=0>
>>>  for
>>> this.
>>>
>>>
>>>
>>> On Tue, Jun 2, 2020 at 11:06 PM Oleg Shirokobrod <
>>> [email protected]> wrote:
>>>
>>> Yes. At the time of computing only 1d observation (VectorXd) is known.
>>>
>>>
>>>
>>> On Tue, Jun 2, 2020 at 9:42 PM Rasmus Munk Larsen <[email protected]>
>>> wrote:
>>>
>>> OK, so b is declared as VectorXf or some other type with
>>> ColsAtCompileTime=1?
>>>
>>>
>>>
>>> On Tue, Jun 2, 2020 at 11:27 AM Oleg Shirokobrod <
>>> [email protected]> wrote:
>>>
>>>
>>>
>>> Yes, b is measured spectrum that is 1d array. I have to get x for 1d
>>> array at a time. I fit sum of peak models to 1d rhs. 1d array of peak model
>>> values is one column of matrix A.
>>>
>>>
>>>
>>> On Tue 2. Jun 2020 at 20.06, Rasmus Munk Larsen <[email protected]>
>>> wrote:
>>>
>>> Why do you say that? You could be solving for multiple right-hand sides.
>>> Is b know to have 1 column at compile time?
>>>
>>>
>>>
>>> On Tue, Jun 2, 2020 at 1:31 AM Oleg Shirokobrod <
>>> [email protected]> wrote:
>>>
>>> Hi Rasmus,
>>>
>>>
>>>
>>> I have just tested COD decomposition in Eigen library. It arises the
>>> same problem. This is defect of Eigen decomposition module type reduction
>>> of result of solve method.  If
>>>
>>>  template <typename T> Matrix<T, Dynamic, Dynamic>  A; and ArraXd b;,
>>> than x = A.solve(b) should be of type  <typename T> Matrix<T, Dynamic, 1.>.
>>>
>>>
>>>
>>> I like the idea to use COD as an alternative to QR or SVD and I added
>>> this option to my code.
>>>
>>>
>>>
>>>
>>>
>>> On Tue, Jun 2, 2020 at 10:36 AM Oleg Shirokobrod <
>>> [email protected]> wrote:
>>>
>>> Rasmus, I wiil have a look at COD. Brad, I did not try CppAD.I am
>>> working in given framework: ceres nonlinear least squares solver + ceres
>>> autodiff + Eigen decomposition modules SVD or QR. The problem is not just
>>> on autodiff side. The problem is that Eigen decomposition modul does not
>>> work properly with autodiff type variable.
>>>
>>>
>>>
>>> Thank you everybody for advice.
>>>
>>>
>>>
>>> On Mon, Jun 1, 2020 at 8:41 PM Rasmus Munk Larsen <[email protected]>
>>> wrote:
>>>
>>>
>>>
>>>
>>>
>>> On Mon, Jun 1, 2020 at 10:33 AM Patrik Huber <[email protected]>
>>> wrote:
>>>
>>> Hi Rasmus,
>>>
>>>
>>>
>>> This is slightly off-topic to this thread here, but it would be great if
>>> you added your COD to the list/table of decompositions in Eigen:
>>> https://eigen.tuxfamily.org/dox/group__TopicLinearAlgebraDecompositions.html
>>> <https://eur03.safelinks.protection.outlook.com/?url=https%3A%2F%2Feigen.tuxfamily.org%2Fdox%2Fgroup__TopicLinearAlgebraDecompositions.html&data=01%7C01%7Ctobias.wood%40kcl.ac.uk%7C9b7731b3d2c24c6ea7e908d808af4522%7C8370cf1416f34c16b83c724071654356%7C0&sdata=BeutduNEeXIXTOtbc8%2BfWXS3FnlTvzEQq0yPrJ7nUOo%3D&reserved=0>
>>>
>>>
>>> First, it would make it easier for people to find, and second, it would
>>> also help a lot to see on that page how the algorithm compares to the
>>> others, to be able to choose it appropriately.
>>>
>>>
>>> Good point. Will do.
>>>
>>>
>>>
>>>
>>>
>>>
>>> Unrelated: @All/Maintainers: It seems like lots (all) of the images on
>>> the documentation website are broken? At least for me. E.g.:
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>> Best wishes,
>>>
>>> Patrik
>>>
>>>
>>>
>>> On Mon, 1 Jun 2020 at 17:59, Rasmus Munk Larsen <[email protected]>
>>> wrote:
>>>
>>> Hi Oleg and Sameer,
>>>
>>>
>>>
>>> A faster option than SVD, but more robust than QR (since it also handles
>>> the under-determined case) is the complete orthogonal decomposition that I
>>> implemented in Eigen a few years ago.
>>>
>>>
>>> https://eigen.tuxfamily.org/dox/classEigen_1_1CompleteOrthogonalDecomposition.html
>>> <https://eur03.safelinks.protection.outlook.com/?url=https%3A%2F%2Feigen.tuxfamily.org%2Fdox%2FclassEigen_1_1CompleteOrthogonalDecomposition.html&data=01%7C01%7Ctobias.wood%40kcl.ac.uk%7C9b7731b3d2c24c6ea7e908d808af4522%7C8370cf1416f34c16b83c724071654356%7C0&sdata=4ALzcdxWY8wDOlejWGXr9DfIUg%2FGV%2B9CnWkoozLWMSU%3D&reserved=0>
>>>
>>> (Looks like the docstring is broken - oops!)
>>>
>>> It appears to also be available in the 3.3 branch:
>>> https://gitlab.com/libeigen/eigen/-/blob/3.3/Eigen/src/QR/CompleteOrthogonalDecomposition.h
>>> <https://eur03.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgitlab.com%2Flibeigen%2Feigen%2F-%2Fblob%2F3.3%2FEigen%2Fsrc%2FQR%2FCompleteOrthogonalDecomposition.h&data=01%7C01%7Ctobias.wood%40kcl.ac.uk%7C9b7731b3d2c24c6ea7e908d808af4522%7C8370cf1416f34c16b83c724071654356%7C0&sdata=F4uktFTL%2BeQ%2BOqeURPZ%2FoOaoReqnH1hU2CobNC%2BNxHk%3D&reserved=0>
>>>
>>> Rasmus
>>>
>>>
>>>
>>> On Mon, Jun 1, 2020 at 6:57 AM Sameer Agarwal <[email protected]>
>>> wrote:
>>>
>>> Oleg,
>>>
>>> Two ideas:
>>>
>>>
>>>
>>> 1. You may have an easier time using QR factorization instead of SVD to
>>> solve your least squares problem.
>>>
>>> 2.  But you can do better, instead of trying to solve linear least
>>> squares problem involving a matrix of Jets, you are better off, solving the
>>> linear least squares problem on the scalars, and then using the implicit
>>> function theorem
>>> <https://eur03.safelinks.protection.outlook.com/?url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FImplicit_function_theorem&data=01%7C01%7Ctobias.wood%40kcl.ac.uk%7C9b7731b3d2c24c6ea7e908d808af4522%7C8370cf1416f34c16b83c724071654356%7C0&sdata=wACe44wQ0vA%2BVFojAnCxvAnvRkgps4y2sIcl0d1wLC4%3D&reserved=0>
>>> to compute the derivative w.r.t the parameters and then applying the chain
>>> rule.
>>>
>>>
>>>
>>> i.e., start with min |A x = b|
>>>
>>>
>>>
>>> the solution satisfies the equation
>>>
>>>
>>>
>>> A'A x - A'b = 0.
>>>
>>>
>>>
>>> solve this equation to get the optimal value of x, and then compute the
>>> jacobian of this equation w.r.t A, b and x. and apply the implicit theorem.
>>>
>>>
>>>
>>> Sameer
>>>
>>>
>>>
>>>
>>>
>>> On Mon, Jun 1, 2020 at 4:46 AM Oleg Shirokobrod <
>>> [email protected]> wrote:
>>>
>>> Hi list, I am using Eigen 3.3.7 release with ceres solver 1.14.0 with
>>> autodiff Jet data type and I have some problems. I need to solve linear
>>> least square subproblem within variable projection algorithm, namely I need
>>> to solve LLS equation
>>>
>>> A(p)*x = b
>>>
>>> Where matrix A(p) depends on nonlinear parameters p:
>>>
>>> x(p) = pseudo-inverse(A(p))*b;
>>>
>>> x(p) will be optimized in nonlinear least squares fitting, so I need
>>> Jcobian. Rhs b is measured vector of doubles, e.g. VectorXd. In order to
>>> use ceres's autodiff p must be of Jet type. Ceres provides corresponding
>>> traits for binary operations
>>>
>>>
>>>
>>> #if EIGEN_VERSION_AT_LEAST(3, 3, 0)
>>> // Specifying the return type of binary operations between Jets and
>>> scalar types
>>> // allows you to perform matrix/array operations with Eigen matrices and
>>> arrays
>>> // such as addition, subtraction, multiplication, and division where one
>>> Eigen
>>> // matrix/array is of type Jet and the other is a scalar type. This
>>> improves
>>> // performance by using the optimized scalar-to-Jet binary operations but
>>> // is only available on Eigen versions >= 3.3
>>> template <typename BinaryOp, typename T, int N>
>>> struct ScalarBinaryOpTraits<ceres::Jet<T, N>, T, BinaryOp> {
>>>   typedef ceres::Jet<T, N> ReturnType;
>>> };
>>> template <typename BinaryOp, typename T, int N>
>>> struct ScalarBinaryOpTraits<T, ceres::Jet<T, N>, BinaryOp> {
>>>   typedef ceres::Jet<T, N> ReturnType;
>>> };
>>> #endif  // EIGEN_VERSION_AT_LEAST(3, 3, 0)
>>>
>>>
>>>
>>> There two problems.
>>>
>>> 1. Small problem. In a function "RealScalar threshold() const" in
>>> SCDbase.h I have to replace "return m_usePrescribedThreshold ?
>>> m_prescribedThreshold
>>>                                     : diagSize*
>>> NumTraits<Scalar>::epsilon();" with "return m_usePrescribedThreshold ?
>>> m_prescribedThreshold
>>>                                     : Scalar(diagSize)*
>>> NumTraits<Scalar>::epsilon();"
>>>
>>> This fix is similar Gael's fix of Bug 1403
>>> <https://eur03.safelinks.protection.outlook.com/?url=http%3A%2F%2Feigen.tuxfamily.org%2Fbz%2Fshow_bug.cgi%3Fid%3D1403&data=01%7C01%7Ctobias.wood%40kcl.ac.uk%7C9b7731b3d2c24c6ea7e908d808af4522%7C8370cf1416f34c16b83c724071654356%7C0&sdata=xcVjY1p2d8oscbHsEuiqRMdNPzGOGGI%2BLb%2FOqZUWrec%3D&reserved=0>
>>>
>>> 2. It is less trivial. I expect that x(p) = pseudo-inverse(A(p))*b; is
>>> vector of Jet. And it is actually true for e.g SVD decompoazition
>>>
>>> x(p) = VSU^T * b.
>>>
>>> But if I use
>>>
>>> JcobySVD<Matrix<Jet<double, 2>, Dynamic, Dynamic>> svd(A);
>>>
>>> x(p) = svd.solve(b),
>>>
>>> I got error message.
>>>
>>> Here code for reproducing the error
>>>
>>>
>>>
>>> // test_svd_jet.cpp
>>>
>>> #include <ceres/jet.h>
>>>
>>> using ceres::Jet;
>>>
>>>
>>>
>>> int test_svd_jet()
>>> {
>>>
>>>     typedef Matrix<Jet<double, 2>, Dynamic, Dynamic> Mat;
>>>     typedef Matrix<Jet<double, 2>, Dynamic, 1> Vec;
>>>      Mat A = MatrixXd::Random(3, 2).cast <Jet<double, 2>>();
>>>      VectorXd b = VectorXd::Random(3);
>>>
>>>      JacobiSVD<Mat> svd(A, ComputeThinU | ComputeThinV);
>>>      int l_rank = svd.rank();
>>>      Vec c = svd.matrixV().leftCols(l_rank)
>>>          * svd.singularValues().head(l_rank).asDiagonal().inverse()
>>>          * svd.matrixU().leftCols(l_rank).adjoint() * b; // *
>>>
>>>      Vec c1 = svd.solve(b.cast<Jet<double, 2>>()); // **
>>>
>>>      Vec c2 = svd.solve(b); // ***
>>>
>>>      return 0;
>>> }
>>>
>>> // End test_svd_jet.cpp
>>>
>>>
>>>
>>> // * and // ** work fine an give the same results. // *** fails with VS
>>> 2019 error message
>>>
>>> Eigen\src\Core\functors\AssignmentFunctors.h(24,1):
>>>
>>> error C2679: binary '=': no operator found which takes
>>> a right-hand operand of type 'const SrcScalar'
>>> (or there is no acceptable conversion)
>>>
>>> The error points to line //***. I thing that solution is of type
>>> VectorXd instead of Vec and there is problem with assignment of double to
>>> Jet. Derivatives are lost either. It should work similar to complex type.
>>> If A is complex matrix and b is real vector, x must be complex. There is
>>> something wrong with Type deduction in SVD or QR decomposition.
>>>
>>>
>>>
>>> Do you have any idea of how to fix it.
>>>
>>>
>>>
>>> Best regards,
>>>
>>>
>>>
>>> Oleg Shirokobrod
>>>
>>>
>>>
>>>

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