blob: b6ac64571a1c6174e74fdf1ab99d4ea942ae60f2 [file] [log] [blame]
 // Copyright ©2018 The Gonum Authors. All rights reserved. // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. package mat_test import ( "fmt" "log" "gonum.org/v1/gonum/mat" ) func ExampleEigenSym() { a := mat.NewSymDense(2, []float64{ 7, 0.5, 0.5, 1, }) fmt.Printf("A = %v\n\n", mat.Formatted(a, mat.Prefix(" "))) var eigsym mat.EigenSym ok := eigsym.Factorize(a, true) if !ok { log.Fatal("Symmetric eigendecomposition failed") } fmt.Printf("Eigenvalues of A:\n%1.3f\n\n", eigsym.Values(nil)) var ev mat.Dense eigsym.VectorsTo(&ev) fmt.Printf("Eigenvectors of A:\n%1.3f\n\n", mat.Formatted(&ev)) // Output: // A = ⎡ 7 0.5⎤ // ⎣0.5 1⎦ // // Eigenvalues of A: // [0.959 7.041] // // Eigenvectors of A: // ⎡ 0.082 -0.997⎤ // ⎣-0.997 -0.082⎦ // } func ExampleEigen() { a := mat.NewDense(2, 2, []float64{ 1, -1, 1, 1, }) fmt.Printf("A = %v\n\n", mat.Formatted(a, mat.Prefix(" "))) var eig mat.Eigen ok := eig.Factorize(a, mat.EigenLeft) if !ok { log.Fatal("Eigendecomposition failed") } fmt.Printf("Eigenvalues of A:\n%v\n", eig.Values(nil)) // Output: // A = ⎡ 1 -1⎤ // ⎣ 1 1⎦ // // Eigenvalues of A: // [(1+1i) (1-1i)] }