/*
* Distributes A in such a way that
* Layer 0 <- A(:, 0:(n/h - 1))
* Layer 1 <- A(:, (n/h):(2n/h - 1))
* .
* .
* .
* Layer h-1 <- A(:, ((h-1)n/h):n)
*/
void DistributeCols
( const mpi::Comm& depthComm,
const DistMatrix<double,MC,MR>& A,
DistMatrix<double,MC,MR>& B )
{
const Grid& meshGrid = A.Grid();
const int meshSize = meshGrid.Size();
const int depthSize = mpi::CommSize( depthComm );
const int depthRank = mpi::CommRank( depthComm );
const int sendCount = A.LocalHeight()*A.LocalWidth();
const int recvCount = sendCount / depthSize;
// For now, we will make B as large as A...
// TODO: NOT DO THIS
if( A.LocalHeight() != A.LocalLDim() )
throw std::logic_error("Local height did not match local ldim");
B.Empty();
B.AlignWith( A );
Zeros( A.Height(), A.Width(), B );
// Scatter
const int localColOffset = (A.LocalWidth()/depthSize)*depthRank;
mpi::Scatter
( A.LockedLocalBuffer(), recvCount,
B.LocalBuffer(0,localColOffset), recvCount, 0, depthComm );
}
// Broadcast a matrix from the root grid to the others
void DepthBroadcast
( const mpi::Comm& depthComm,
const DistMatrix<double,MC,MR>& A,
DistMatrix<double,MC,MR>& B )
{
const int rank = mpi::CommRank(mpi::COMM_WORLD);
const Grid& meshGrid = A.Grid();
const int meshSize = meshGrid.Size();
const int depthRank = rank / meshSize;
const int localSize = A.LocalHeight()*A.LocalWidth();
if( A.LocalHeight() != A.LocalLDim() )
throw std::logic_error("Leading dimension did not match local height");
B.Empty();
B.AlignWith( A );
B.ResizeTo( A.Height(), A.Width() );
// Have the root pack the broadcast data
if( depthRank == 0 )
MemCopy( B.LocalBuffer(), A.LockedLocalBuffer(), localSize );
// Broadcast from the root
mpi::Broadcast( B.LocalBuffer(), localSize, 0, depthComm );
}
inline void HermitianSVD
( UpperOrLower uplo,
DistMatrix<F>& A, DistMatrix<typename Base<F>::type,VR,STAR>& s,
DistMatrix<F>& U, DistMatrix<F>& V )
{
#ifndef RELEASE
PushCallStack("HermitianSVD");
#endif
typedef typename Base<F>::type R;
// Grab an eigenvalue decomposition of A
HermitianEig( uplo, A, s, V );
// Redistribute the singular values into an [MR,* ] distribution
const Grid& grid = A.Grid();
DistMatrix<R,MR,STAR> s_MR_STAR( grid );
s_MR_STAR.AlignWith( V );
s_MR_STAR = s;
// Set the singular values to the absolute value of the eigenvalues
const int numLocalVals = s.LocalHeight();
for( int iLocal=0; iLocal<numLocalVals; ++iLocal )
{
const R sigma = s.GetLocal(iLocal,0);
s.SetLocal(iLocal,0,Abs(sigma));
}
// Copy V into U (flipping the sign as necessary)
U.AlignWith( V );
U.ResizeTo( V.Height(), V.Width() );
const int localHeight = V.LocalHeight();
const int localWidth = V.LocalWidth();
for( int jLocal=0; jLocal<localWidth; ++jLocal )
{
const R sigma = s_MR_STAR.GetLocal( jLocal, 0 );
F* UCol = U.LocalBuffer( 0, jLocal );
const F* VCol = V.LockedLocalBuffer( 0, jLocal );
if( sigma >= 0 )
for( int iLocal=0; iLocal<localHeight; ++iLocal )
UCol[iLocal] = VCol[iLocal];
else
for( int iLocal=0; iLocal<localHeight; ++iLocal )
UCol[iLocal] = -VCol[iLocal];
}
#ifndef RELEASE
PopCallStack();
#endif
}
inline const DistMatrix<T,MD,STAR,Int>&
DistMatrix<T,MD,STAR,Int>::operator=( const DistMatrix<T,STAR,STAR,Int>& A )
{
#ifndef RELEASE
PushCallStack("[MD,* ] = [* ,* ]");
this->AssertNotLockedView();
this->AssertSameGrid( A );
if( this->Viewing() )
this->AssertSameSize( A );
#endif
if( !this->Viewing() )
this->ResizeTo( A.Height(), A.Width() );
if( this->Participating() )
{
const Int lcm = this->grid_->LCM();
const Int colShift = this->ColShift();
const Int width = this->Width();
const Int localHeight = this->LocalHeight();
const T* ALocalBuffer = A.LockedLocalBuffer();
const Int ALDim = A.LocalLDim();
T* thisLocalBuffer = this->LocalBuffer();
const Int thisLDim = this->LocalLDim();
#ifdef HAVE_OPENMP
#pragma omp parallel for
#endif
for( Int j=0; j<width; ++j )
{
T* destCol = &thisLocalBuffer[j*thisLDim];
const T* sourceCol = &ALocalBuffer[colShift+j*ALDim];
for( Int iLocal=0; iLocal<localHeight; ++iLocal )
destCol[iLocal] = sourceCol[iLocal*lcm];
}
}
#ifndef RELEASE
PopCallStack();
#endif
return *this;
}
inline void AddInLocalData
( const DistMatrix<F,VC,STAR>& X1, DistMatrix<F,STAR,STAR>& Z )
{
#ifndef RELEASE
PushCallStack("internal::AddInLocalData");
#endif
const int width = X1.Width();
const int localHeight = X1.LocalHeight();
const int stride = X1.Grid().Size();
const int offset = X1.ColShift();
for( int j=0; j<width; ++j )
{
F* ZColBuffer = Z.LocalBuffer(0,j);
const F* X1ColBuffer = X1.LockedLocalBuffer(0,j);
for( int iLocal=0; iLocal<localHeight; ++iLocal )
ZColBuffer[offset+stride*iLocal] += X1ColBuffer[iLocal];
}
#ifndef RELEASE
PopCallStack();
#endif
}
// Reduce across depth to get end result C
void SumContributions
( mpi::Comm& depthComm,
const DistMatrix<double,MC,MR>& APartial,
DistMatrix<double,MC,MR>& A )
{
const int rank = mpi::CommRank( mpi::COMM_WORLD );
const Grid& meshGrid = APartial.Grid();
A.Empty();
A.AlignWith( APartial );
A.ResizeTo( APartial.Height(), APartial.Width() );
if( APartial.LocalHeight() != APartial.LocalLDim() )
throw std::logic_error
("APartial did not have matching local height/ldim");
if( A.LocalHeight() != A.LocalLDim() )
throw std::logic_error("A did not have matching local height/ldim");
const int dataSize = APartial.LocalHeight()*APartial.LocalWidth();
mpi::AllReduce
( APartial.LockedLocalBuffer(), A.LocalBuffer(), dataSize,
mpi::SUM, depthComm );
}