Fig. 11From: Newton–Raphson preconditioner for Krylov type solvers on GPU devicesHistories of condition number and residual norm of BFGS–GCR on GR_30_30. The left vertical axis shows the residual norm \(\Vert \mathbf {r} \Vert _2 / \Vert \mathbf {b} \Vert _2\), the right vertical axis shows the condition number in logarithmic scale and the horizontal axis shows the number of iterationsBack to article page