Actual source code: ssils.c
1: #include "src/complementarity/impls/ssls/ssls.h"
3: /*------------------------------------------------------------*/
6: static int TaoSolve_SSILS(TAO_SOLVER tao, void *solver)
7: {
8: TAO_SSLS *ssls = (TAO_SSLS *)solver;
9: // TaoLinearSolver *lsolver;
10: TaoVec *x, *l, *u, *ff, *dpsi, *d, *w;
11: TaoMat *J;
12: double psi, ndpsi, normd, innerd, t=0;
13: double delta, rho;
14: int iter=0, info;
15: TaoTerminateReason reason;
16: TaoTruth flag;
18: TaoFunctionBegin;
20: // Assume that Setup has been called!
21: // Set the structure for the Jacobian and create a linear solver.
22:
23: delta = ssls->delta;
24: rho = ssls->rho;
26: info = TaoGetSolution(tao, &x); CHKERRQ(info);
27: l=ssls->xl;
28: u=ssls->xu;
29: info = TaoEvaluateVariableBounds(tao,l,u); CHKERRQ(info);
30: info = x->Median(l,x,u); CHKERRQ(info);
31: info = TaoGetJacobian(tao, &J); CHKERRQ(info);
33: ff = ssls->ff;
34: dpsi = ssls->dpsi;
35: d = ssls->d;
36: w = ssls->w;
38: info = TaoSetMeritFunction(tao, Tao_SSLS_Function, Tao_SSLS_FunctionGradient,
39: TAO_NULL, TAO_NULL, ssls); CHKERRQ(info);
41: info = J->SetStructure(TAOMAT_UNSYMMETRIC); CHKERRQ(info);
43: // Calculate the function value and fischer function value at the
44: // current iterate
45: info = TaoComputeMeritFunctionGradient(tao, x, &psi, dpsi); CHKERRQ(info);
46: info = dpsi->Norm2(&ndpsi); CHKERRQ(info);
48: while (1) {
49: info=PetscLogInfo((tao, "TaoSolve_SSILS: %d: merit: %5.4e, ndpsi: %5.4e\n",
50: iter, ssls->merit, ndpsi)); CHKERRQ(info);
51: // Check the termination criteria
52: info = TaoMonitor(tao,iter++,ssls->merit,ndpsi,0.0,t,&reason);
53: CHKERRQ(info);
54: if (reason!=TAO_CONTINUE_ITERATING) break;
56: // Calculate direction. (Really negative of newton direction. Therefore,
57: // rest of the code uses -d.)
58: info = TaoPreLinearSolve(tao, J); CHKERRQ(info);
59: info = TaoLinearSolve(tao, J, ff, d, &flag); CHKERRQ(info);
60: info = d->Norm2(&normd); CHKERRQ(info);
61: info = d->Dot(dpsi, &innerd); CHKERRQ(info);
63: // Make sure that we have a descent direction
64: if (innerd <= delta*pow(normd, rho)) {
65: info = PetscLogInfo((tao, "TaoSolve_SSILS: %d: newton direction not descent\n", iter)); CHKERRQ(info);
66: info = d->CopyFrom(dpsi); CHKERRQ(info);
67: info = d->Dot(dpsi, &innerd); CHKERRQ(info);
68: }
70: info = d->Negate(); CHKERRQ(info);
71: innerd = -innerd;
73: t = 1;
74: info = TaoLineSearchApply(tao, x, dpsi, d, w,
75: &psi, &t, &tao->lsflag); CHKERRQ(info);
76: info = dpsi->Norm2(&ndpsi);
77: }
79: TaoFunctionReturn(0);
80: }
82: /* ---------------------------------------------------------- */
86: int TaoCreate_SSILS(TAO_SOLVER tao)
87: {
88: TAO_SSLS *ssls;
89: int info;
91: TaoFunctionBegin;
93: info = TaoNew(TAO_SSLS,&ssls); CHKERRQ(info);
94: info = PetscLogObjectMemory(tao, sizeof(TAO_SSLS)); CHKERRQ(info);
96: ssls->delta = 1e-10;
97: ssls->rho = 2.1;
99: info=TaoSetTaoSolveRoutine(tao,TaoSolve_SSILS,(void*)ssls); CHKERRQ(info);
100: info=TaoSetTaoSetUpDownRoutines(tao,TaoSetUp_SSLS,TaoSetDown_SSLS); CHKERRQ(info);
101: info=TaoSetTaoOptionsRoutine(tao,TaoSetOptions_SSLS); CHKERRQ(info);
102: info=TaoSetTaoViewRoutine(tao,TaoView_SSLS); CHKERRQ(info);
104: info = TaoCreateArmijoLineSearch(tao); CHKERRQ(info);
106: info = TaoSetMaximumIterates(tao,2000); CHKERRQ(info);
107: info = TaoSetMaximumFunctionEvaluations(tao,4000); CHKERRQ(info);
109: info = TaoSetTolerances(tao,0,0,0,0); CHKERRQ(info);
110: info = TaoSetGradientTolerances(tao,1.0e-16,0.0,0.0); CHKERRQ(info);
111: info = TaoSetFunctionLowerBound(tao,1.0e-8); CHKERRQ(info);
113: TaoFunctionReturn(0);
114: }