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authorStanislaw Halik <sthalik@misaki.pl>2019-03-03 21:09:10 +0100
committerStanislaw Halik <sthalik@misaki.pl>2019-03-03 21:10:13 +0100
commitf0238cfb6997c4acfc2bd200de7295f3fa36968f (patch)
treeb215183760e4f615b9c1dabc1f116383b72a1b55 /eigen/doc/special_examples/Tutorial_sparse_example_details.cpp
parent543edd372a5193d04b3de9f23c176ab439e51b31 (diff)
don't index Eigen
Diffstat (limited to 'eigen/doc/special_examples/Tutorial_sparse_example_details.cpp')
-rw-r--r--eigen/doc/special_examples/Tutorial_sparse_example_details.cpp44
1 files changed, 0 insertions, 44 deletions
diff --git a/eigen/doc/special_examples/Tutorial_sparse_example_details.cpp b/eigen/doc/special_examples/Tutorial_sparse_example_details.cpp
deleted file mode 100644
index bc18b01..0000000
--- a/eigen/doc/special_examples/Tutorial_sparse_example_details.cpp
+++ /dev/null
@@ -1,44 +0,0 @@
-#include <Eigen/Sparse>
-#include <vector>
-#include <QImage>
-
-typedef Eigen::SparseMatrix<double> SpMat; // declares a column-major sparse matrix type of double
-typedef Eigen::Triplet<double> T;
-
-void insertCoefficient(int id, int i, int j, double w, std::vector<T>& coeffs,
- Eigen::VectorXd& b, const Eigen::VectorXd& boundary)
-{
- int n = int(boundary.size());
- int id1 = i+j*n;
-
- if(i==-1 || i==n) b(id) -= w * boundary(j); // constrained coefficient
- else if(j==-1 || j==n) b(id) -= w * boundary(i); // constrained coefficient
- else coeffs.push_back(T(id,id1,w)); // unknown coefficient
-}
-
-void buildProblem(std::vector<T>& coefficients, Eigen::VectorXd& b, int n)
-{
- b.setZero();
- Eigen::ArrayXd boundary = Eigen::ArrayXd::LinSpaced(n, 0,M_PI).sin().pow(2);
- for(int j=0; j<n; ++j)
- {
- for(int i=0; i<n; ++i)
- {
- int id = i+j*n;
- insertCoefficient(id, i-1,j, -1, coefficients, b, boundary);
- insertCoefficient(id, i+1,j, -1, coefficients, b, boundary);
- insertCoefficient(id, i,j-1, -1, coefficients, b, boundary);
- insertCoefficient(id, i,j+1, -1, coefficients, b, boundary);
- insertCoefficient(id, i,j, 4, coefficients, b, boundary);
- }
- }
-}
-
-void saveAsBitmap(const Eigen::VectorXd& x, int n, const char* filename)
-{
- Eigen::Array<unsigned char,Eigen::Dynamic,Eigen::Dynamic> bits = (x*255).cast<unsigned char>();
- QImage img(bits.data(), n,n,QImage::Format_Indexed8);
- img.setColorCount(256);
- for(int i=0;i<256;i++) img.setColor(i,qRgb(i,i,i));
- img.save(filename);
-}