magma_int_t
magma_spgmres( magma_s_sparse_matrix A, magma_s_vector b, magma_s_vector *x,
magma_s_solver_par *solver_par,
magma_s_preconditioner *precond_par ){
// prepare solver feedback
solver_par->solver = Magma_PGMRES;
solver_par->numiter = 0;
solver_par->info = 0;
// local variables
float c_zero = MAGMA_S_ZERO, c_one = MAGMA_S_ONE,
c_mone = MAGMA_S_NEG_ONE;
magma_int_t dofs = A.num_rows;
magma_int_t i, j, k, m = 0;
magma_int_t restart = min( dofs-1, solver_par->restart );
magma_int_t ldh = restart+1;
float nom, rNorm, RNorm, nom0, betanom, r0 = 0.;
// CPU workspace
//magma_setdevice(0);
float *H, *HH, *y, *h1;
magma_smalloc_pinned( &H, (ldh+1)*ldh );
magma_smalloc_pinned( &y, ldh );
magma_smalloc_pinned( &HH, ldh*ldh );
magma_smalloc_pinned( &h1, ldh );
// GPU workspace
magma_s_vector r, q, q_t, z, z_t, t;
magma_s_vinit( &t, Magma_DEV, dofs, c_zero );
magma_s_vinit( &r, Magma_DEV, dofs, c_zero );
magma_s_vinit( &q, Magma_DEV, dofs*(ldh+1), c_zero );
magma_s_vinit( &z, Magma_DEV, dofs*(ldh+1), c_zero );
magma_s_vinit( &z_t, Magma_DEV, dofs, c_zero );
q_t.memory_location = Magma_DEV;
q_t.val = NULL;
q_t.num_rows = q_t.nnz = dofs;
float *dy, *dH = NULL;
if (MAGMA_SUCCESS != magma_smalloc( &dy, ldh ))
return MAGMA_ERR_DEVICE_ALLOC;
if (MAGMA_SUCCESS != magma_smalloc( &dH, (ldh+1)*ldh ))
return MAGMA_ERR_DEVICE_ALLOC;
// GPU stream
magma_queue_t stream[2];
magma_event_t event[1];
magma_queue_create( &stream[0] );
magma_queue_create( &stream[1] );
magma_event_create( &event[0] );
magmablasSetKernelStream(stream[0]);
magma_sscal( dofs, c_zero, x->val, 1 ); // x = 0
magma_scopy( dofs, b.val, 1, r.val, 1 ); // r = b
nom0 = betanom = magma_snrm2( dofs, r.val, 1 ); // nom0= || r||
nom = nom0 * nom0;
solver_par->init_res = nom0;
H(1,0) = MAGMA_S_MAKE( nom0, 0. );
magma_ssetvector(1, &H(1,0), 1, &dH(1,0), 1);
if ( (r0 = nom0 * RTOLERANCE ) < ATOLERANCE )
r0 = solver_par->epsilon;
if ( nom < r0 )
return MAGMA_SUCCESS;
//Chronometry
real_Double_t tempo1, tempo2;
magma_device_sync(); tempo1=magma_wtime();
if( solver_par->verbose > 0 ){
solver_par->res_vec[0] = nom0;
solver_par->timing[0] = 0.0;
}
// start iteration
for( solver_par->numiter= 1; solver_par->numiter<solver_par->maxiter;
solver_par->numiter++ ){
for(k=1; k<=restart; k++) {
magma_scopy(dofs, r.val, 1, q(k-1), 1); // q[0] = 1.0/||r||
magma_sscal(dofs, 1./H(k,k-1), q(k-1), 1); // (to be fused)
q_t.val = q(k-1);
magmablasSetKernelStream(stream[0]);
// preconditioner
// z[k] = M^(-1) q(k)
magma_s_applyprecond_left( A, q_t, &t, precond_par );
magma_s_applyprecond_right( A, t, &z_t, precond_par );
magma_scopy(dofs, z_t.val, 1, z(k-1), 1);
// r = A q[k]
magma_s_spmv( c_one, A, z_t, c_zero, r );
// if (solver_par->ortho == Magma_MGS ) {
// modified Gram-Schmidt
for (i=1; i<=k; i++) {
H(i,k) =magma_sdot(dofs, q(i-1), 1, r.val, 1);
// H(i,k) = q[i] . r
magma_saxpy(dofs,-H(i,k), q(i-1), 1, r.val, 1);
// r = r - H(i,k) q[i]
}
H(k+1,k) = MAGMA_S_MAKE( magma_snrm2(dofs, r.val, 1), 0. ); // H(k+1,k) = ||r||
/*}else if (solver_par->ortho == Magma_FUSED_CGS ) {
// fusing sgemv with snrm2 in classical Gram-Schmidt
magmablasSetKernelStream(stream[0]);
magma_scopy(dofs, r.val, 1, q(k), 1);
// dH(1:k+1,k) = q[0:k] . r
magmablas_sgemv(MagmaTrans, dofs, k+1, c_one, q(0),
dofs, r.val, 1, c_zero, &dH(1,k), 1);
// r = r - q[0:k-1] dH(1:k,k)
magmablas_sgemv(MagmaNoTrans, dofs, k, c_mone, q(0),
dofs, &dH(1,k), 1, c_one, r.val, 1);
// 1) dH(k+1,k) = sqrt( dH(k+1,k) - dH(1:k,k) )
magma_scopyscale( dofs, k, r.val, q(k), &dH(1,k) );
// 2) q[k] = q[k] / dH(k+1,k)
magma_event_record( event[0], stream[0] );
magma_queue_wait_event( stream[1], event[0] );
magma_sgetvector_async(k+1, &dH(1,k), 1, &H(1,k), 1, stream[1]);
// asynch copy dH(1:(k+1),k) to H(1:(k+1),k)
} else {
// classical Gram-Schmidt (default)
// > explicitly calling magmabls
magmablasSetKernelStream(stream[0]);
magmablas_sgemv(MagmaTrans, dofs, k, c_one, q(0),
dofs, r.val, 1, c_zero, &dH(1,k), 1);
// dH(1:k,k) = q[0:k-1] . r
#ifndef SNRM2SCALE
// start copying dH(1:k,k) to H(1:k,k)
magma_event_record( event[0], stream[0] );
magma_queue_wait_event( stream[1], event[0] );
magma_sgetvector_async(k, &dH(1,k), 1, &H(1,k),
1, stream[1]);
#endif
// r = r - q[0:k-1] dH(1:k,k)
magmablas_sgemv(MagmaNoTrans, dofs, k, c_mone, q(0),
dofs, &dH(1,k), 1, c_one, r.val, 1);
#ifdef SNRM2SCALE
magma_scopy(dofs, r.val, 1, q(k), 1);
// q[k] = r / H(k,k-1)
magma_snrm2scale(dofs, q(k), dofs, &dH(k+1,k) );
// dH(k+1,k) = sqrt(r . r) and r = r / dH(k+1,k)
magma_event_record( event[0], stream[0] );
// start sending dH(1:k,k) to H(1:k,k)
magma_queue_wait_event( stream[1], event[0] );
// can we keep H(k+1,k) on GPU and combine?
magma_sgetvector_async(k+1, &dH(1,k), 1, &H(1,k), 1, stream[1]);
#else
H(k+1,k) = MAGMA_S_MAKE( magma_snrm2(dofs, r.val, 1), 0. );
// H(k+1,k) = sqrt(r . r)
if( k<solver_par->restart ){
magmablasSetKernelStream(stream[0]);
magma_scopy(dofs, r.val, 1, q(k), 1);
// q[k] = 1.0/H[k][k-1] r
magma_sscal(dofs, 1./H(k+1,k), q(k), 1);
// (to be fused)
}
#endif
}*/
/* Minimization of || b-Ax || in H_k */
for (i=1; i<=k; i++) {
HH(k,i) = magma_cblas_sdot( i+1, &H(1,k), 1, &H(1,i), 1 );
}
h1[k] = H(1,k)*H(1,0);
if (k != 1){
for (i=1; i<k; i++) {
HH(k,i) = HH(k,i)/HH(i,i);//
for (m=i+1; m<=k; m++){
HH(k,m) -= HH(k,i) * HH(m,i) * HH(i,i);
}
h1[k] -= h1[i] * HH(k,i);
}
}
y[k] = h1[k]/HH(k,k);
if (k != 1)
for (i=k-1; i>=1; i--) {
y[i] = h1[i]/HH(i,i);
for (j=i+1; j<=k; j++)
y[i] -= y[j] * HH(j,i);
}
m = k;
rNorm = fabs(MAGMA_S_REAL(H(k+1,k)));
}/* Minimization done */
// compute solution approximation
magma_ssetmatrix(m, 1, y+1, m, dy, m );
magma_sgemv(MagmaNoTrans, dofs, m, c_one, z(0), dofs, dy, 1,
c_one, x->val, 1);
// compute residual
magma_s_spmv( c_mone, A, *x, c_zero, r ); // r = - A * x
magma_saxpy(dofs, c_one, b.val, 1, r.val, 1); // r = r + b
H(1,0) = MAGMA_S_MAKE( magma_snrm2(dofs, r.val, 1), 0. );
// RNorm = H[1][0] = || r ||
RNorm = MAGMA_S_REAL( H(1,0) );
betanom = fabs(RNorm);
if( solver_par->verbose > 0 ){
magma_device_sync(); tempo2=magma_wtime();
if( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
if ( betanom < r0 ) {
break;
}
}
magma_device_sync(); tempo2=magma_wtime();
solver_par->runtime = (real_Double_t) tempo2-tempo1;
float residual;
magma_sresidual( A, b, *x, &residual );
solver_par->iter_res = betanom;
solver_par->final_res = residual;
if( solver_par->numiter < solver_par->maxiter){
solver_par->info = 0;
}else if( solver_par->init_res > solver_par->final_res ){
if( solver_par->verbose > 0 ){
if( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
solver_par->info = -2;
}
else{
if( solver_par->verbose > 0 ){
if( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
solver_par->info = -1;
}
// free pinned memory
magma_free_pinned( H );
magma_free_pinned( y );
magma_free_pinned( HH );
magma_free_pinned( h1 );
// free GPU memory
magma_free(dy);
if (dH != NULL ) magma_free(dH);
magma_s_vfree(&t);
magma_s_vfree(&r);
magma_s_vfree(&q);
magma_s_vfree(&z);
magma_s_vfree(&z_t);
// free GPU streams and events
magma_queue_destroy( stream[0] );
magma_queue_destroy( stream[1] );
magma_event_destroy( event[0] );
magmablasSetKernelStream(NULL);
return MAGMA_SUCCESS;
} /* magma_spgmres */
extern "C" magma_int_t
magma_scg_merge(
magma_s_sparse_matrix A, magma_s_vector b, magma_s_vector *x,
magma_s_solver_par *solver_par,
magma_queue_t queue )
{
// set queue for old dense routines
magma_queue_t orig_queue;
magmablasGetKernelStream( &orig_queue );
// prepare solver feedback
solver_par->solver = Magma_CGMERGE;
solver_par->numiter = 0;
solver_par->info = MAGMA_SUCCESS;
// some useful variables
float c_zero = MAGMA_S_ZERO, c_one = MAGMA_S_ONE;
magma_int_t dofs = A.num_rows;
// GPU stream
magma_queue_t stream[2];
magma_event_t event[1];
magma_queue_create( &stream[0] );
magma_queue_create( &stream[1] );
magma_event_create( &event[0] );
// GPU workspace
magma_s_vector r, d, z;
magma_s_vinit( &r, Magma_DEV, dofs, c_zero, queue );
magma_s_vinit( &d, Magma_DEV, dofs, c_zero, queue );
magma_s_vinit( &z, Magma_DEV, dofs, c_zero, queue );
float *d1, *d2, *skp;
d1 = NULL;
d2 = NULL;
skp = NULL;
magma_int_t stat_dev = 0, stat_cpu = 0;
stat_dev += magma_smalloc( &d1, dofs*(1) );
stat_dev += magma_smalloc( &d2, dofs*(1) );
// array for the parameters
stat_dev += magma_smalloc( &skp, 6 );
// skp = [alpha|beta|gamma|rho|tmp1|tmp2]
if( stat_dev != 0 ){
magma_free( d1 );
magma_free( d2 );
magma_free( skp );
printf("error: memory allocation.\n");
return MAGMA_ERR_DEVICE_ALLOC;
}
// solver variables
float alpha, beta, gamma, rho, tmp1, *skp_h;
float nom, nom0, r0, betanom, den;
// solver setup
magma_sscal( dofs, c_zero, x->dval, 1) ; // x = 0
magma_scopy( dofs, b.dval, 1, r.dval, 1 ); // r = b
magma_scopy( dofs, b.dval, 1, d.dval, 1 ); // d = b
nom0 = betanom = magma_snrm2( dofs, r.dval, 1 );
nom = nom0 * nom0; // nom = r' * r
magma_s_spmv( c_one, A, d, c_zero, z, queue ); // z = A d
den = MAGMA_S_REAL( magma_sdot(dofs, d.dval, 1, z.dval, 1) ); // den = d'* z
solver_par->init_res = nom0;
// array on host for the parameters
stat_cpu += magma_smalloc_cpu( &skp_h, 6 );
if( stat_cpu != 0 ){
magma_free( d1 );
magma_free( d2 );
magma_free( skp );
magma_free_cpu( skp_h );
printf("error: memory allocation.\n");
return MAGMA_ERR_HOST_ALLOC;
}
alpha = rho = gamma = tmp1 = c_one;
beta = magma_sdot(dofs, r.dval, 1, r.dval, 1);
skp_h[0]=alpha;
skp_h[1]=beta;
skp_h[2]=gamma;
skp_h[3]=rho;
skp_h[4]=tmp1;
skp_h[5]=MAGMA_S_MAKE(nom, 0.0);
magma_ssetvector( 6, skp_h, 1, skp, 1 );
if ( (r0 = nom * solver_par->epsilon) < ATOLERANCE )
r0 = ATOLERANCE;
if ( nom < r0 ) {
magmablasSetKernelStream( orig_queue );
return MAGMA_SUCCESS;
}
// check positive definite
if (den <= 0.0) {
printf("Operator A is not postive definite. (Ar,r) = %f\n", den);
magmablasSetKernelStream( orig_queue );
return MAGMA_NONSPD;
solver_par->info = MAGMA_NONSPD;;
}
//Chronometry
real_Double_t tempo1, tempo2;
tempo1 = magma_sync_wtime( queue );
if ( solver_par->verbose > 0 ) {
solver_par->res_vec[0] = (real_Double_t) nom0;
solver_par->timing[0] = 0.0;
}
// start iteration
for( solver_par->numiter= 1; solver_par->numiter<solver_par->maxiter;
solver_par->numiter++ ) {
magmablasSetKernelStream(stream[0]);
// computes SpMV and dot product
magma_scgmerge_spmv1( A, d1, d2, d.dval, z.dval, skp, queue );
// updates x, r, computes scalars and updates d
magma_scgmerge_xrbeta( dofs, d1, d2, x->dval, r.dval, d.dval, z.dval, skp, queue );
// check stopping criterion (asynchronous copy)
magma_sgetvector_async( 1 , skp+1, 1,
skp_h+1, 1, stream[1] );
betanom = sqrt(MAGMA_S_REAL(skp_h[1]));
if ( solver_par->verbose > 0 ) {
tempo2 = magma_sync_wtime( queue );
if ( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
if ( betanom < r0 ) {
break;
}
}
tempo2 = magma_sync_wtime( queue );
solver_par->runtime = (real_Double_t) tempo2-tempo1;
float residual;
magma_sresidual( A, b, *x, &residual, queue );
solver_par->iter_res = betanom;
solver_par->final_res = residual;
if ( solver_par->numiter < solver_par->maxiter) {
solver_par->info = MAGMA_SUCCESS;
} else if ( solver_par->init_res > solver_par->final_res ) {
if ( solver_par->verbose > 0 ) {
if ( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
solver_par->info = MAGMA_SLOW_CONVERGENCE;
}
else {
if ( solver_par->verbose > 0 ) {
if ( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
solver_par->info = MAGMA_DIVERGENCE;
}
magma_s_vfree(&r, queue );
magma_s_vfree(&z, queue );
magma_s_vfree(&d, queue );
magma_free( d1 );
magma_free( d2 );
magma_free( skp );
magma_free_cpu( skp_h );
magmablasSetKernelStream( orig_queue );
return MAGMA_SUCCESS;
} /* magma_scg_merge */
magma_int_t
magma_sbicgstab( magma_s_sparse_matrix A, magma_s_vector b, magma_s_vector *x,
magma_s_solver_par *solver_par ){
// prepare solver feedback
solver_par->solver = Magma_BICGSTAB;
solver_par->numiter = 0;
solver_par->info = 0;
// some useful variables
float c_zero = MAGMA_S_ZERO, c_one = MAGMA_S_ONE,
c_mone = MAGMA_S_NEG_ONE;
magma_int_t dofs = A.num_rows;
// workspace
magma_s_vector r,rr,p,v,s,t;
magma_s_vinit( &r, Magma_DEV, dofs, c_zero );
magma_s_vinit( &rr, Magma_DEV, dofs, c_zero );
magma_s_vinit( &p, Magma_DEV, dofs, c_zero );
magma_s_vinit( &v, Magma_DEV, dofs, c_zero );
magma_s_vinit( &s, Magma_DEV, dofs, c_zero );
magma_s_vinit( &t, Magma_DEV, dofs, c_zero );
// solver variables
float alpha, beta, omega, rho_old, rho_new;
float nom, betanom, nom0, r0, den, res;
// solver setup
magma_sscal( dofs, c_zero, x->val, 1) ; // x = 0
magma_scopy( dofs, b.val, 1, r.val, 1 ); // r = b
magma_scopy( dofs, b.val, 1, rr.val, 1 ); // rr = b
nom0 = betanom = magma_snrm2( dofs, r.val, 1 ); // nom = || r ||
nom = nom0*nom0;
rho_old = omega = alpha = MAGMA_S_MAKE( 1.0, 0. );
solver_par->init_res = nom0;
magma_s_spmv( c_one, A, r, c_zero, v ); // z = A r
den = MAGMA_S_REAL( magma_sdot(dofs, v.val, 1, r.val, 1) ); // den = z' * r
if ( (r0 = nom * solver_par->epsilon) < ATOLERANCE )
r0 = ATOLERANCE;
if ( nom < r0 )
return MAGMA_SUCCESS;
// check positive definite
if (den <= 0.0) {
printf("Operator A is not postive definite. (Ar,r) = %f\n", den);
return -100;
}
//Chronometry
real_Double_t tempo1, tempo2;
magma_device_sync(); tempo1=magma_wtime();
if( solver_par->verbose > 0 ){
solver_par->res_vec[0] = nom0;
solver_par->timing[0] = 0.0;
}
// start iteration
for( solver_par->numiter= 1; solver_par->numiter<solver_par->maxiter;
solver_par->numiter++ ){
rho_new = magma_sdot( dofs, rr.val, 1, r.val, 1 ); // rho=<rr,r>
beta = rho_new/rho_old * alpha/omega; // beta=rho/rho_old *alpha/omega
magma_sscal( dofs, beta, p.val, 1 ); // p = beta*p
magma_saxpy( dofs, c_mone * omega * beta, v.val, 1 , p.val, 1 );
// p = p-omega*beta*v
magma_saxpy( dofs, c_one, r.val, 1, p.val, 1 ); // p = p+r
magma_s_spmv( c_one, A, p, c_zero, v ); // v = Ap
alpha = rho_new / magma_sdot( dofs, rr.val, 1, v.val, 1 );
magma_scopy( dofs, r.val, 1 , s.val, 1 ); // s=r
magma_saxpy( dofs, c_mone * alpha, v.val, 1 , s.val, 1 ); // s=s-alpha*v
magma_s_spmv( c_one, A, s, c_zero, t ); // t=As
omega = magma_sdot( dofs, t.val, 1, s.val, 1 ) // omega = <s,t>/<t,t>
/ magma_sdot( dofs, t.val, 1, t.val, 1 );
magma_saxpy( dofs, alpha, p.val, 1 , x->val, 1 ); // x=x+alpha*p
magma_saxpy( dofs, omega, s.val, 1 , x->val, 1 ); // x=x+omega*s
magma_scopy( dofs, s.val, 1 , r.val, 1 ); // r=s
magma_saxpy( dofs, c_mone * omega, t.val, 1 , r.val, 1 ); // r=r-omega*t
res = betanom = magma_snrm2( dofs, r.val, 1 );
nom = betanom*betanom;
rho_old = rho_new; // rho_old=rho
if( solver_par->verbose > 0 ){
magma_device_sync(); tempo2=magma_wtime();
if( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) res;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
if ( res/nom0 < solver_par->epsilon ) {
break;
}
}
magma_device_sync(); tempo2=magma_wtime();
solver_par->runtime = (real_Double_t) tempo2-tempo1;
float residual;
magma_sresidual( A, b, *x, &residual );
solver_par->iter_res = res;
solver_par->final_res = residual;
if( solver_par->numiter < solver_par->maxiter){
solver_par->info = 0;
}else if( solver_par->init_res > solver_par->final_res ){
if( solver_par->verbose > 0 ){
if( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
solver_par->info = -2;
}
else{
if( solver_par->verbose > 0 ){
if( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
solver_par->info = -1;
}
magma_s_vfree(&r);
magma_s_vfree(&rr);
magma_s_vfree(&p);
magma_s_vfree(&v);
magma_s_vfree(&s);
magma_s_vfree(&t);
return MAGMA_SUCCESS;
} /* magma_sbicgstab */
magma_int_t
magma_sbicgstab_merge( magma_s_sparse_matrix A, magma_s_vector b,
magma_s_vector *x, magma_s_solver_par *solver_par ){
// prepare solver feedback
solver_par->solver = Magma_BICGSTABMERGE;
solver_par->numiter = 0;
solver_par->info = 0;
// some useful variables
float c_zero = MAGMA_S_ZERO, c_one = MAGMA_S_ONE;
magma_int_t dofs = A.num_rows;
// GPU stream
magma_queue_t stream[2];
magma_event_t event[1];
magma_queue_create( &stream[0] );
magma_queue_create( &stream[1] );
magma_event_create( &event[0] );
// workspace
magma_s_vector q, r,rr,p,v,s,t;
float *d1, *d2, *skp;
magma_smalloc( &d1, dofs*(2) );
magma_smalloc( &d2, dofs*(2) );
// array for the parameters
magma_smalloc( &skp, 8 );
// skp = [alpha|beta|omega|rho_old|rho|nom|tmp1|tmp2]
magma_s_vinit( &q, Magma_DEV, dofs*6, c_zero );
// q = rr|r|p|v|s|t
rr.memory_location = Magma_DEV; rr.val = NULL; rr.num_rows = rr.nnz = dofs;
r.memory_location = Magma_DEV; r.val = NULL; r.num_rows = r.nnz = dofs;
p.memory_location = Magma_DEV; p.val = NULL; p.num_rows = p.nnz = dofs;
v.memory_location = Magma_DEV; v.val = NULL; v.num_rows = v.nnz = dofs;
s.memory_location = Magma_DEV; s.val = NULL; s.num_rows = s.nnz = dofs;
t.memory_location = Magma_DEV; t.val = NULL; t.num_rows = t.nnz = dofs;
rr.val = q(0);
r.val = q(1);
p.val = q(2);
v.val = q(3);
s.val = q(4);
t.val = q(5);
// solver variables
float alpha, beta, omega, rho_old, rho_new, *skp_h;
float nom, nom0, betanom, r0, den;
// solver setup
magma_sscal( dofs, c_zero, x->val, 1) ; // x = 0
magma_scopy( dofs, b.val, 1, q(0), 1 ); // rr = b
magma_scopy( dofs, b.val, 1, q(1), 1 ); // r = b
rho_new = magma_sdot( dofs, r.val, 1, r.val, 1 ); // rho=<rr,r>
nom = MAGMA_S_REAL(magma_sdot( dofs, r.val, 1, r.val, 1 ));
nom0 = betanom = sqrt(nom); // nom = || r ||
rho_old = omega = alpha = MAGMA_S_MAKE( 1.0, 0. );
beta = rho_new;
solver_par->init_res = nom0;
// array on host for the parameters
magma_smalloc_cpu( &skp_h, 8 );
skp_h[0]=alpha;
skp_h[1]=beta;
skp_h[2]=omega;
skp_h[3]=rho_old;
skp_h[4]=rho_new;
skp_h[5]=MAGMA_S_MAKE(nom, 0.0);
magma_ssetvector( 8, skp_h, 1, skp, 1 );
magma_s_spmv( c_one, A, r, c_zero, v ); // z = A r
den = MAGMA_S_REAL( magma_sdot(dofs, v.val, 1, r.val, 1) );// den = z dot r
if ( (r0 = nom * solver_par->epsilon) < ATOLERANCE )
r0 = ATOLERANCE;
if ( nom < r0 )
return MAGMA_SUCCESS;
// check positive definite
if (den <= 0.0) {
printf("Operator A is not postive definite. (Ar,r) = %f\n", den);
return -100;
}
//Chronometry
real_Double_t tempo1, tempo2;
magma_device_sync(); tempo1=magma_wtime();
if( solver_par->verbose > 0 ){
solver_par->res_vec[0] = nom0;
solver_par->timing[0] = 0.0;
}
// start iteration
for( solver_par->numiter= 1; solver_par->numiter<solver_par->maxiter;
solver_par->numiter++ ){
magmablasSetKernelStream(stream[0]);
// computes p=r+beta*(p-omega*v)
magma_sbicgmerge1( dofs, skp, v.val, r.val, p.val );
magma_s_spmv( c_one, A, p, c_zero, v ); // v = Ap
magma_smdotc( dofs, 1, q.val, v.val, d1, d2, skp );
magma_sbicgmerge4( 1, skp );
magma_sbicgmerge2( dofs, skp, r.val, v.val, s.val ); // s=r-alpha*v
magma_s_spmv( c_one, A, s, c_zero, t ); // t=As
magma_smdotc( dofs, 2, q.val+4*dofs, t.val, d1, d2, skp+6 );
magma_sbicgmerge4( 2, skp );
magma_sbicgmerge3( dofs, skp, p.val, s.val, // x=x+alpha*p+omega*s
t.val, x->val, r.val ); // r=s-omega*t
magma_smdotc( dofs, 2, q.val, r.val, d1, d2, skp+4);
magma_sbicgmerge4( 3, skp );
// check stopping criterion (asynchronous copy)
magma_sgetvector_async( 1 , skp+5, 1,
skp_h+5, 1, stream[1] );
betanom = sqrt(MAGMA_S_REAL(skp_h[5]));
if( solver_par->verbose > 0 ){
magma_device_sync(); tempo2=magma_wtime();
if( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
if ( betanom < r0 ) {
break;
}
}
magma_device_sync(); tempo2=magma_wtime();
solver_par->runtime = (real_Double_t) tempo2-tempo1;
float residual;
magma_sresidual( A, b, *x, &residual );
solver_par->iter_res = betanom;
solver_par->final_res = residual;
if( solver_par->numiter < solver_par->maxiter){
solver_par->info = 0;
}else if( solver_par->init_res > solver_par->final_res ){
if( solver_par->verbose > 0 ){
if( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
solver_par->info = -2;
}
else{
if( solver_par->verbose > 0 ){
if( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
solver_par->info = -1;
}
magma_s_vfree(&q); // frees all vectors
magma_free(d1);
magma_free(d2);
magma_free( skp );
magma_free_cpu( skp_h );
return MAGMA_SUCCESS;
} /* sbicgstab_merge */
extern "C" magma_int_t
magma_sbpcg(
magma_s_matrix A, magma_s_matrix b, magma_s_matrix *x,
magma_s_solver_par *solver_par,
magma_s_preconditioner *precond_par,
magma_queue_t queue )
{
magma_int_t info = 0;
magma_int_t i, num_vecs = b.num_rows/A.num_rows;
// prepare solver feedback
solver_par->solver = Magma_PCG;
solver_par->numiter = 0;
solver_par->spmv_count = 0;
solver_par->info = MAGMA_SUCCESS;
// local variables
float c_zero = MAGMA_S_ZERO, c_one = MAGMA_S_ONE;
magma_int_t dofs = A.num_rows;
// GPU workspace
magma_s_matrix r={Magma_CSR}, rt={Magma_CSR}, p={Magma_CSR}, q={Magma_CSR}, h={Magma_CSR};
// solver variables
float *alpha={0}, *beta={0};
alpha = NULL;
beta = NULL;
float *nom={0}, *nom0={0}, *r0={0}, *gammaold={0}, *gammanew={0}, *den={0}, *res={0}, *residual={0};
nom = NULL;
nom0 = NULL;
r0 = NULL;
gammaold = NULL;
gammanew = NULL;
den = NULL;
res = NULL;
residual = NULL;
CHECK( magma_smalloc_cpu(&alpha, num_vecs));
CHECK( magma_smalloc_cpu(&beta, num_vecs));
CHECK( magma_smalloc_cpu(&residual, num_vecs));
CHECK( magma_smalloc_cpu(&nom, num_vecs));
CHECK( magma_smalloc_cpu(&nom0, num_vecs));
CHECK( magma_smalloc_cpu(&r0, num_vecs));
CHECK( magma_smalloc_cpu(&gammaold, num_vecs));
CHECK( magma_smalloc_cpu(&gammanew, num_vecs));
CHECK( magma_smalloc_cpu(&den, num_vecs));
CHECK( magma_smalloc_cpu(&res, num_vecs));
CHECK( magma_smalloc_cpu(&residual, num_vecs));
CHECK( magma_svinit( &r, Magma_DEV, dofs*num_vecs, 1, c_zero, queue ));
CHECK( magma_svinit( &rt, Magma_DEV, dofs*num_vecs, 1, c_zero, queue ));
CHECK( magma_svinit( &p, Magma_DEV, dofs*num_vecs, 1, c_zero, queue ));
CHECK( magma_svinit( &q, Magma_DEV, dofs*num_vecs, 1, c_zero, queue ));
CHECK( magma_svinit( &h, Magma_DEV, dofs*num_vecs, 1, c_zero, queue ));
// solver setup
CHECK( magma_sresidualvec( A, b, *x, &r, nom0, queue));
// preconditioner
CHECK( magma_s_applyprecond_left( MagmaNoTrans, A, r, &rt, precond_par, queue ));
CHECK( magma_s_applyprecond_right( MagmaNoTrans, A, rt, &h, precond_par, queue ));
magma_scopy( dofs*num_vecs, h.dval, 1, p.dval, 1, queue ); // p = h
for( i=0; i<num_vecs; i++) {
nom[i] = MAGMA_S_REAL( magma_sdot( dofs, r(i), 1, h(i), 1, queue ) );
nom0[i] = magma_snrm2( dofs, r(i), 1, queue );
}
CHECK( magma_s_spmv( c_one, A, p, c_zero, q, queue )); // q = A p
for( i=0; i<num_vecs; i++)
den[i] = MAGMA_S_REAL( magma_sdot( dofs, p(i), 1, q(i), 1, queue ) ); // den = p dot q
solver_par->init_res = nom0[0];
if ( (r0[0] = nom[0] * solver_par->rtol) < ATOLERANCE )
r0[0] = ATOLERANCE;
// check positive definite
if (den[0] <= 0.0) {
printf("Operator A is not postive definite. (Ar,r) = %f\n", den[0]);
info = MAGMA_NONSPD;
goto cleanup;
}
if ( nom[0] < r0[0] ) {
solver_par->final_res = solver_par->init_res;
solver_par->iter_res = solver_par->init_res;
goto cleanup;
}
//Chronometry
real_Double_t tempo1, tempo2;
tempo1 = magma_sync_wtime( queue );
if ( solver_par->verbose > 0 ) {
solver_par->res_vec[0] = (real_Double_t)nom0[0];
solver_par->timing[0] = 0.0;
}
solver_par->numiter = 0;
solver_par->spmv_count = 0;
// start iteration
do
{
solver_par->numiter++;
// preconditioner
CHECK( magma_s_applyprecond_left( MagmaNoTrans, A, r, &rt, precond_par, queue ));
CHECK( magma_s_applyprecond_right( MagmaNoTrans, A, rt, &h, precond_par, queue ));
for( i=0; i<num_vecs; i++)
gammanew[i] = MAGMA_S_REAL( magma_sdot( dofs, r(i), 1, h(i), 1, queue ) ); // gn = < r,h>
if ( solver_par->numiter==1 ) {
magma_scopy( dofs*num_vecs, h.dval, 1, p.dval, 1, queue ); // p = h
} else {
for( i=0; i<num_vecs; i++) {
beta[i] = MAGMA_S_MAKE(gammanew[i]/gammaold[i], 0.); // beta = gn/go
magma_sscal( dofs, beta[i], p(i), 1, queue ); // p = beta*p
magma_saxpy( dofs, c_one, h(i), 1, p(i), 1, queue ); // p = p + h
}
}
CHECK( magma_s_spmv( c_one, A, p, c_zero, q, queue )); // q = A p
solver_par->spmv_count++;
// magma_s_bspmv_tuned( dofs, num_vecs, c_one, A, p.dval, c_zero, q.dval, queue );
for( i=0; i<num_vecs; i++) {
den[i] = MAGMA_S_REAL(magma_sdot( dofs, p(i), 1, q(i), 1, queue) );
// den = p dot q
alpha[i] = MAGMA_S_MAKE(gammanew[i]/den[i], 0.);
magma_saxpy( dofs, alpha[i], p(i), 1, x->dval+dofs*i, 1, queue ); // x = x + alpha p
magma_saxpy( dofs, -alpha[i], q(i), 1, r(i), 1, queue ); // r = r - alpha q
gammaold[i] = gammanew[i];
res[i] = magma_snrm2( dofs, r(i), 1, queue );
}
if ( solver_par->verbose > 0 ) {
tempo2 = magma_sync_wtime( queue );
if ( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) res[0];
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
if ( res[0]/nom0[0] < solver_par->rtol ) {
break;
}
}
while ( solver_par->numiter+1 <= solver_par->maxiter );
tempo2 = magma_sync_wtime( queue );
solver_par->runtime = (real_Double_t) tempo2-tempo1;
CHECK( magma_sresidual( A, b, *x, residual, queue ));
solver_par->iter_res = res[0];
solver_par->final_res = residual[0];
if ( solver_par->numiter < solver_par->maxiter ) {
solver_par->info = MAGMA_SUCCESS;
} else if ( solver_par->init_res > solver_par->final_res ) {
if ( solver_par->verbose > 0 ) {
if ( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) res[0];
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
info = MAGMA_SLOW_CONVERGENCE;
if( solver_par->iter_res < solver_par->rtol*solver_par->init_res ){
info = MAGMA_SUCCESS;
}
}
else {
if ( solver_par->verbose > 0 ) {
if ( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) res[0];
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
info = MAGMA_DIVERGENCE;
}
for( i=0; i<num_vecs; i++) {
printf("%.4e ",res[i]);
}
printf("\n");
for( i=0; i<num_vecs; i++) {
printf("%.4e ",residual[i]);
}
printf("\n");
cleanup:
magma_smfree(&r, queue );
magma_smfree(&rt, queue );
magma_smfree(&p, queue );
magma_smfree(&q, queue );
magma_smfree(&h, queue );
magma_free_cpu(alpha);
magma_free_cpu(beta);
magma_free_cpu(nom);
magma_free_cpu(nom0);
magma_free_cpu(r0);
magma_free_cpu(gammaold);
magma_free_cpu(gammanew);
magma_free_cpu(den);
magma_free_cpu(res);
solver_par->info = info;
return info;
} /* magma_sbpcg */
extern "C" magma_int_t
magma_scg(
magma_s_sparse_matrix A, magma_s_vector b, magma_s_vector *x,
magma_s_solver_par *solver_par,
magma_queue_t queue )
{
// set queue for old dense routines
magma_queue_t orig_queue;
magmablasGetKernelStream( &orig_queue );
// prepare solver feedback
solver_par->solver = Magma_CG;
solver_par->numiter = 0;
solver_par->info = MAGMA_SUCCESS;
// local variables
float c_zero = MAGMA_S_ZERO, c_one = MAGMA_S_ONE;
magma_int_t dofs = A.num_rows;
// GPU workspace
magma_s_vector r, p, q;
magma_s_vinit( &r, Magma_DEV, dofs, c_zero, queue );
magma_s_vinit( &p, Magma_DEV, dofs, c_zero, queue );
magma_s_vinit( &q, Magma_DEV, dofs, c_zero, queue );
// solver variables
float alpha, beta;
float nom, nom0, r0, betanom, betanomsq, den;
// solver setup
magma_sscal( dofs, c_zero, x->dval, 1) ; // x = 0
magma_scopy( dofs, b.dval, 1, r.dval, 1 ); // r = b
magma_scopy( dofs, b.dval, 1, p.dval, 1 ); // p = b
nom0 = betanom = magma_snrm2( dofs, r.dval, 1 );
nom = nom0 * nom0; // nom = r' * r
magma_s_spmv( c_one, A, p, c_zero, q, queue ); // q = A p
den = MAGMA_S_REAL( magma_sdot(dofs, p.dval, 1, q.dval, 1) );// den = p dot q
solver_par->init_res = nom0;
if ( (r0 = nom * solver_par->epsilon) < ATOLERANCE )
r0 = ATOLERANCE;
if ( nom < r0 ) {
magmablasSetKernelStream( orig_queue );
return MAGMA_SUCCESS;
}
// check positive definite
if (den <= 0.0) {
printf("Operator A is not postive definite. (Ar,r) = %f\n", den);
magmablasSetKernelStream( orig_queue );
return MAGMA_NONSPD;
solver_par->info = MAGMA_NONSPD;
}
//Chronometry
real_Double_t tempo1, tempo2;
tempo1 = magma_sync_wtime( queue );
if ( solver_par->verbose > 0 ) {
solver_par->res_vec[0] = (real_Double_t)nom0;
solver_par->timing[0] = 0.0;
}
// start iteration
for( solver_par->numiter= 1; solver_par->numiter<solver_par->maxiter;
solver_par->numiter++ ) {
alpha = MAGMA_S_MAKE(nom/den, 0.);
magma_saxpy(dofs, alpha, p.dval, 1, x->dval, 1); // x = x + alpha p
magma_saxpy(dofs, -alpha, q.dval, 1, r.dval, 1); // r = r - alpha q
betanom = magma_snrm2(dofs, r.dval, 1); // betanom = || r ||
betanomsq = betanom * betanom; // betanoms = r' * r
if ( solver_par->verbose > 0 ) {
tempo2 = magma_sync_wtime( queue );
if ( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
if ( betanom < r0 ) {
break;
}
beta = MAGMA_S_MAKE(betanomsq/nom, 0.); // beta = betanoms/nom
magma_sscal(dofs, beta, p.dval, 1); // p = beta*p
magma_saxpy(dofs, c_one, r.dval, 1, p.dval, 1); // p = p + r
magma_s_spmv( c_one, A, p, c_zero, q, queue ); // q = A p
den = MAGMA_S_REAL(magma_sdot(dofs, p.dval, 1, q.dval, 1));
// den = p dot q
nom = betanomsq;
}
tempo2 = magma_sync_wtime( queue );
solver_par->runtime = (real_Double_t) tempo2-tempo1;
float residual;
magma_sresidual( A, b, *x, &residual, queue );
solver_par->final_res = residual;
if ( solver_par->numiter < solver_par->maxiter) {
solver_par->info = MAGMA_SUCCESS;
} else if ( solver_par->init_res > solver_par->final_res ) {
if ( solver_par->verbose > 0 ) {
if ( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
solver_par->info = MAGMA_SLOW_CONVERGENCE;
}
else {
if ( solver_par->verbose > 0 ) {
if ( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) betanom;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
solver_par->info = MAGMA_DIVERGENCE;
}
magma_s_vfree(&r, queue );
magma_s_vfree(&p, queue );
magma_s_vfree(&q, queue );
magmablasSetKernelStream( orig_queue );
return MAGMA_SUCCESS;
} /* magma_scg */
/* ////////////////////////////////////////////////////////////////////////////
-- testing any solver
*/
int main( int argc, char** argv )
{
magma_int_t info = 0;
TESTING_INIT();
magma_queue_t queue=NULL;
magma_queue_create( 0, &queue );
float one = MAGMA_S_MAKE(1.0, 0.0);
float zero = MAGMA_S_MAKE(0.0, 0.0);
magma_s_matrix A={Magma_CSR}, B_d={Magma_CSR};
magma_s_matrix x={Magma_CSR}, b={Magma_CSR};
int i=1;
while( i < argc ) {
if ( strcmp("LAPLACE2D", argv[i]) == 0 && i+1 < argc ) { // Laplace test
i++;
magma_int_t laplace_size = atoi( argv[i] );
CHECK( magma_sm_5stencil( laplace_size, &A, queue ));
} else { // file-matrix test
CHECK( magma_s_csr_mtx( &A, argv[i], queue ));
}
printf( "\n# matrix info: %d-by-%d with %d nonzeros\n\n",
int(A.num_rows), int(A.num_cols), int(A.nnz) );
magma_int_t n = A.num_rows;
CHECK( magma_smtransfer( A, &B_d, Magma_CPU, Magma_DEV, queue ));
// vectors and initial guess
CHECK( magma_svinit( &b, Magma_DEV, A.num_cols, 1, zero, queue ));
CHECK( magma_svinit( &x, Magma_DEV, A.num_cols, 1, one, queue ));
CHECK( magma_sprint_vector( b, 90, 10, queue ));
CHECK( magma_sprint_matrix( A, queue ));
printf("\n\n\n");
CHECK( magma_sprint_matrix( B_d, queue ));
float res;
res = magma_snrm2(n, b.dval, 1, queue );
printf("norm0: %f\n", res);
CHECK( magma_s_spmv( one, B_d, x, zero, b, queue )); // b = A x
CHECK( magma_sprint_vector( b, 0, 100, queue ));
CHECK( magma_sprint_vector( b, b.num_rows-10, 10, queue ));
res = magma_snrm2( n, b.dval, 1, queue );
printf("norm: %f\n", res);
CHECK( magma_sresidual( B_d, x, b, &res, queue));
printf("res: %f\n", res);
magma_smfree(&B_d, queue );
magma_smfree(&A, queue );
magma_smfree(&x, queue );
magma_smfree(&b, queue );
i++;
}
cleanup:
magma_smfree(&A, queue );
magma_smfree(&B_d, queue );
magma_smfree(&x, queue );
magma_smfree(&b, queue );
magma_queue_destroy( queue );
magma_finalize();
return info;
}
magma_int_t
magma_spcg( magma_s_sparse_matrix A, magma_s_vector b, magma_s_vector *x,
magma_s_solver_par *solver_par,
magma_s_preconditioner *precond_par ){
// prepare solver feedback
solver_par->solver = Magma_PCG;
solver_par->numiter = 0;
solver_par->info = 0;
// local variables
float c_zero = MAGMA_S_ZERO, c_one = MAGMA_S_ONE;
magma_int_t dofs = A.num_rows;
// GPU workspace
magma_s_vector r, rt, p, q, h;
magma_s_vinit( &r, Magma_DEV, dofs, c_zero );
magma_s_vinit( &rt, Magma_DEV, dofs, c_zero );
magma_s_vinit( &p, Magma_DEV, dofs, c_zero );
magma_s_vinit( &q, Magma_DEV, dofs, c_zero );
magma_s_vinit( &h, Magma_DEV, dofs, c_zero );
// solver variables
float alpha, beta;
float nom, nom0, r0, gammaold, gammanew, den, res;
// solver setup
magma_sscal( dofs, c_zero, x->val, 1) ; // x = 0
magma_scopy( dofs, b.val, 1, r.val, 1 ); // r = b
// preconditioner
magma_s_applyprecond_left( A, r, &rt, precond_par );
magma_s_applyprecond_right( A, rt, &h, precond_par );
magma_scopy( dofs, h.val, 1, p.val, 1 ); // p = h
nom = MAGMA_S_REAL( magma_sdot(dofs, r.val, 1, h.val, 1) );
nom0 = magma_snrm2( dofs, r.val, 1 );
magma_s_spmv( c_one, A, p, c_zero, q ); // q = A p
den = MAGMA_S_REAL( magma_sdot(dofs, p.val, 1, q.val, 1) );// den = p dot q
solver_par->init_res = nom0;
if ( (r0 = nom * solver_par->epsilon) < ATOLERANCE )
r0 = ATOLERANCE;
if ( nom < r0 )
return MAGMA_SUCCESS;
// check positive definite
if (den <= 0.0) {
printf("Operator A is not postive definite. (Ar,r) = %f\n", den);
return -100;
}
//Chronometry
real_Double_t tempo1, tempo2;
magma_device_sync(); tempo1=magma_wtime();
if( solver_par->verbose > 0 ){
solver_par->res_vec[0] = (real_Double_t)nom0;
solver_par->timing[0] = 0.0;
}
// start iteration
for( solver_par->numiter= 1; solver_par->numiter<solver_par->maxiter;
solver_par->numiter++ ){
// preconditioner
magma_s_applyprecond_left( A, r, &rt, precond_par );
magma_s_applyprecond_right( A, rt, &h, precond_par );
gammanew = MAGMA_S_REAL( magma_sdot(dofs, r.val, 1, h.val, 1) );
// gn = < r,h>
if( solver_par->numiter==1 ){
magma_scopy( dofs, h.val, 1, p.val, 1 ); // p = h
}else{
beta = MAGMA_S_MAKE(gammanew/gammaold, 0.); // beta = gn/go
magma_sscal(dofs, beta, p.val, 1); // p = beta*p
magma_saxpy(dofs, c_one, h.val, 1, p.val, 1); // p = p + h
}
magma_s_spmv( c_one, A, p, c_zero, q ); // q = A p
den = MAGMA_S_REAL(magma_sdot(dofs, p.val, 1, q.val, 1));
// den = p dot q
alpha = MAGMA_S_MAKE(gammanew/den, 0.);
magma_saxpy(dofs, alpha, p.val, 1, x->val, 1); // x = x + alpha p
magma_saxpy(dofs, -alpha, q.val, 1, r.val, 1); // r = r - alpha q
gammaold = gammanew;
res = magma_snrm2( dofs, r.val, 1 );
if( solver_par->verbose > 0 ){
magma_device_sync(); tempo2=magma_wtime();
if( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) res;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
if ( res/nom0 < solver_par->epsilon ) {
break;
}
}
magma_device_sync(); tempo2=magma_wtime();
solver_par->runtime = (real_Double_t) tempo2-tempo1;
float residual;
magma_sresidual( A, b, *x, &residual );
solver_par->iter_res = res;
solver_par->final_res = residual;
if( solver_par->numiter < solver_par->maxiter){
solver_par->info = 0;
}else if( solver_par->init_res > solver_par->final_res ){
if( solver_par->verbose > 0 ){
if( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) res;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
solver_par->info = -2;
}
else{
if( solver_par->verbose > 0 ){
if( (solver_par->numiter)%solver_par->verbose==0 ) {
solver_par->res_vec[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) res;
solver_par->timing[(solver_par->numiter)/solver_par->verbose]
= (real_Double_t) tempo2-tempo1;
}
}
solver_par->info = -1;
}
magma_s_vfree(&r);
magma_s_vfree(&rt);
magma_s_vfree(&p);
magma_s_vfree(&q);
magma_s_vfree(&h);
return MAGMA_SUCCESS;
} /* magma_scg */
