inline void pdxxxresid1(ClpPdco *model, const int nlow, const int nupp, const int nfix, int *low, int *upp, int *fix, CoinDenseVector <double> &b, double *bl, double *bu, double d1, double d2, CoinDenseVector <double> &grad, CoinDenseVector <double> &rL, CoinDenseVector <double> &rU, CoinDenseVector <double> &x, CoinDenseVector <double> &x1, CoinDenseVector <double> &x2, CoinDenseVector <double> &y, CoinDenseVector <double> &z1, CoinDenseVector <double> &z2, CoinDenseVector <double> &r1, CoinDenseVector <double> &r2, double *Pinf, double *Dinf) { // Form residuals for the primal and dual equations. // rL, rU are output, but we input them as full vectors // initialized (permanently) with any relevant zeros. // Get some element pointers for efficiency double *x_elts = x.getElements(); double *r2_elts = r2.getElements(); for (int k = 0; k < nfix; k++) x_elts[fix[k]] = 0; r1.clear(); r2.clear(); model->matVecMult( 1, r1, x ); model->matVecMult( 2, r2, y ); for (int k = 0; k < nfix; k++) r2_elts[fix[k]] = 0; r1 = b - r1 - d2 * d2 * y; r2 = grad - r2 - z1; // grad includes d1*d1*x if (nupp > 0) r2 = r2 + z2; for (int k = 0; k < nlow; k++) rL[low[k]] = bl[low[k]] - x[low[k]] + x1[low[k]]; for (int k = 0; k < nupp; k++) rU[upp[k]] = - bu[upp[k]] + x[upp[k]] + x2[upp[k]]; double normL = 0.0; double normU = 0.0; for (int k = 0; k < nlow; k++) if (rL[low[k]] > normL) normL = rL[low[k]]; for (int k = 0; k < nupp; k++) if (rU[upp[k]] > normU) normU = rU[upp[k]]; *Pinf = CoinMax(normL, normU); *Pinf = CoinMax( r1.infNorm() , *Pinf ); *Dinf = r2.infNorm(); *Pinf = CoinMax( *Pinf, 1e-99 ); *Dinf = CoinMax( *Dinf, 1e-99 ); }
void ClpLsqr::do_lsqr(CoinDenseVector< double > &b, double damp, double atol, double btol, double conlim, int itnlim, bool show, Info info, CoinDenseVector< double > &x, int *istop, int *itn, Outfo *outfo, bool precon, CoinDenseVector< double > &Pr) { /** Special version of LSQR for use with pdco.m. It continues with a reduced atol if a pdco-specific test isn't satisfied with the input atol. */ // Initialize. static char term_msg[8][80] = { "The exact solution is x = 0", "The residual Ax - b is small enough, given ATOL and BTOL", "The least squares error is small enough, given ATOL", "The estimated condition number has exceeded CONLIM", "The residual Ax - b is small enough, given machine precision", "The least squares error is small enough, given machine precision", "The estimated condition number has exceeded machine precision", "The iteration limit has been reached" }; // printf("***************** Entering LSQR *************\n"); assert(model_); char str1[100], str2[100], str3[100], str4[100], head1[100], head2[100]; int n = ncols_; // set m,n from lsqr object *itn = 0; *istop = 0; double ctol = 0; if (conlim > 0) ctol = 1 / conlim; double anorm = 0; double acond = 0; double ddnorm = 0; double xnorm = 0; double xxnorm = 0; double z = 0; double cs2 = -1; double sn2 = 0; // Set up the first vectors u and v for the bidiagonalization. // These satisfy beta*u = b, alfa*v = A'u. CoinDenseVector< double > u(b); CoinDenseVector< double > v(n, 0.0); x.clear(); double alfa = 0; double beta = u.twoNorm(); if (beta > 0) { u = (1 / beta) * u; matVecMult(2, v, u); if (precon) v = v * Pr; alfa = v.twoNorm(); } if (alfa > 0) { v.scale(1 / alfa); } CoinDenseVector< double > w(v); double arnorm = alfa * beta; if (arnorm == 0) { printf(" %s\n\n", term_msg[0]); return; } double rhobar = alfa; double phibar = beta; double bnorm = beta; double rnorm = beta; sprintf(head1, " Itn x(1) Function"); sprintf(head2, " Compatible LS Norm A Cond A"); if (show) { printf(" %s%s\n", head1, head2); double test1 = 1; double test2 = alfa / beta; sprintf(str1, "%6d %12.5e %10.3e", *itn, x[0], rnorm); sprintf(str2, " %8.1e %8.1e", test1, test2); printf("%s%s\n", str1, str2); } //---------------------------------------------------------------- // Main iteration loop. //---------------------------------------------------------------- while (*itn < itnlim) { *itn += 1; // Perform the next step of the bidiagonalization to obtain the // next beta, u, alfa, v. These satisfy the relations // beta*u = a*v - alfa*u, // alfa*v = A'*u - beta*v. u.scale((-alfa)); if (precon) { CoinDenseVector< double > pv(v * Pr); matVecMult(1, u, pv); } else { matVecMult(1, u, v); } beta = u.twoNorm(); if (beta > 0) { u.scale((1 / beta)); anorm = sqrt(anorm * anorm + alfa * alfa + beta * beta + damp * damp); v.scale((-beta)); CoinDenseVector< double > vv(n); vv.clear(); matVecMult(2, vv, u); if (precon) vv = vv * Pr; v = v + vv; alfa = v.twoNorm(); if (alfa > 0) v.scale((1 / alfa)); } // Use a plane rotation to eliminate the damping parameter. // This alters the diagonal (rhobar) of the lower-bidiagonal matrix. double rhobar1 = sqrt(rhobar * rhobar + damp * damp); double cs1 = rhobar / rhobar1; double sn1 = damp / rhobar1; double psi = sn1 * phibar; phibar *= cs1; // Use a plane rotation to eliminate the subdiagonal element (beta) // of the lower-bidiagonal matrix, giving an upper-bidiagonal matrix. double rho = sqrt(rhobar1 * rhobar1 + beta * beta); double cs = rhobar1 / rho; double sn = beta / rho; double theta = sn * alfa; rhobar = -cs * alfa; double phi = cs * phibar; phibar = sn * phibar; double tau = sn * phi; // Update x and w. double t1 = phi / rho; double t2 = -theta / rho; // dk = ((1/rho)*w); double w_norm = w.twoNorm(); x = x + t1 * w; w = v + t2 * w; ddnorm = ddnorm + (w_norm / rho) * (w_norm / rho); // if wantvar, var = var + dk.*dk; end // Use a plane rotation on the right to eliminate the // super-diagonal element (theta) of the upper-bidiagonal matrix. // Then use the result to estimate norm(x). double delta = sn2 * rho; double gambar = -cs2 * rho; double rhs = phi - delta * z; double zbar = rhs / gambar; xnorm = sqrt(xxnorm + zbar * zbar); double gamma = sqrt(gambar * gambar + theta * theta); cs2 = gambar / gamma; sn2 = theta / gamma; z = rhs / gamma; xxnorm = xxnorm + z * z; // Test for convergence. // First, estimate the condition of the matrix Abar, // and the norms of rbar and Abar'rbar. acond = anorm * sqrt(ddnorm); double res1 = phibar * phibar; double res2 = res1 + psi * psi; rnorm = sqrt(res1 + res2); arnorm = alfa * fabs(tau); // Now use these norms to estimate certain other quantities, // some of which will be small near a solution. double test1 = rnorm / bnorm; double test2 = arnorm / (anorm * rnorm); double test3 = 1 / acond; t1 = test1 / (1 + anorm * xnorm / bnorm); double rtol = btol + atol * anorm * xnorm / bnorm; // The following tests guard against extremely small values of // atol, btol or ctol. (The user may have set any or all of // the parameters atol, btol, conlim to 0.) // The effect is equivalent to the normal tests using // atol = eps, btol = eps, conlim = 1/eps. if (*itn >= itnlim) *istop = 7; if (1 + test3 <= 1) *istop = 6; if (1 + test2 <= 1) *istop = 5; if (1 + t1 <= 1) *istop = 4; // Allow for tolerances set by the user. if (test3 <= ctol) *istop = 3; if (test2 <= atol) *istop = 2; if (test1 <= rtol) *istop = 1; //------------------------------------------------------------------- // SPECIAL TEST THAT DEPENDS ON pdco.m. // Aname in pdco is iw in lsqr. // dy is x // Other stuff is in info. // We allow for diagonal preconditioning in pdDDD3. //------------------------------------------------------------------- if (*istop > 0) { double r3new = arnorm; double r3ratio = r3new / info.r3norm; double atolold = atol; double atolnew = atol; if (atol > info.atolmin) { if (r3ratio <= 0.1) { // dy seems good // Relax } else if (r3ratio <= 0.5) { // Accept dy but make next one more accurate. atolnew = atolnew * 0.1; } else { // Recompute dy more accurately if (show) { printf("\n "); printf(" \n"); printf(" %5.1f%7d%7.3f", log10(atolold), *itn, r3ratio); } atol = atol * 0.1; atolnew = atol; *istop = 0; } outfo->atolold = atolold; outfo->atolnew = atolnew; outfo->r3ratio = r3ratio; } //------------------------------------------------------------------- // See if it is time to print something. //------------------------------------------------------------------- int prnt = 0; if (n <= 40) prnt = 1; if (*itn <= 10) prnt = 1; if (*itn >= itnlim - 10) prnt = 1; if (*itn % 10 == 0) prnt = 1; if (test3 <= 2 * ctol) prnt = 1; if (test2 <= 10 * atol) prnt = 1; if (test1 <= 10 * rtol) prnt = 1; if (*istop != 0) prnt = 1; if (prnt == 1) { if (show) { sprintf(str1, " %6d %12.5e %10.3e", *itn, x[0], rnorm); sprintf(str2, " %8.1e %8.1e", test1, test2); sprintf(str3, " %8.1e %8.1e", anorm, acond); printf("%s%s%s\n", str1, str2, str3); } } if (*istop > 0) break; } } // End of iteration loop. // Print the stopping condition. if (show) { printf("\n LSQR finished\n"); // disp(msg(istop+1,:)) // disp(' ') printf("%s\n", term_msg[*istop]); sprintf(str1, "istop =%8d itn =%8d", *istop, *itn); sprintf(str2, "anorm =%8.1e acond =%8.1e", anorm, acond); sprintf(str3, "rnorm =%8.1e arnorm =%8.1e", rnorm, arnorm); sprintf(str4, "bnorm =%8.1e xnorm =%8.1e", bnorm, xnorm); printf("%s %s\n", str1, str2); printf("%s %s\n", str3, str4); } }