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c++saveeigendiagonal

How to save Eigen::DiagonalMatrix in MarketIO format in Eigen?

Using Eigen 3.2.1, I am trying to save an Eigen::DiagonalMatrix in MarketIO format as below:

#include <Eigen/Sparse>
#include <Unsupported/Eigen/SparseExtra>
using namespace Eigen;
...

size_t n = XX;
DiagonalMatrix<num_t, Dynamic> W(n);
...
saveMarket(W, "W.txt"); // error propagates from here

However, I am getting the following error:

MarketIO.h|236|error: 'const class Eigen::DiagonalMatrix<double, -1>' has no
member named 'nonZeros'

What is the problem here? Is this implemented at all for Diagonal Matrices?

Thanks in advance for any help.

Solution

  • Okay! The only solution for now with minimal effort is to use the following:

    saveMarketVector(W.diagonal(), "W.txt");