Hello,
The problem: I want to be able to extract different views from within an
Epetra_Vector without creating new memory. My question is whether these
views, when created using a generated map (eg. from a MapColoring) can
be used transparently, eg. for assignment.
The specifics: I am extracting views by coloring maps, as in the following:
double* _dataPtr;
std::vector<int> colors;
// colors filled with NT_GRID_COLOR_T enumeration
_epMapPtr = new Epetra_BlockMap(totalSize, _arraySize, 1, 0,
*_epCommPtr);
_epVectorPtr = new Epetra_Vector(*_epMapPtr);
_epVectorPtr->ExtractView(&_dataPtr);
_epMapColoringPtr =
new Epetra_MapColoring(*_epMapPtr, &colors[0], NT_INVALID_COLOR);
_epInteriorVectorPtr =
new Epetra_Vector(View,
*_epMapColoringPtr->GenerateBlockMap(NT_INTERIOR_COLOR),
_dataPtr);
However, when I try to assign to _epInteriorVectorPtr, eg
Epetra_Vector v;
// fill v with data
*_epInteriorVectorPtr = v;
I am not getting the expected result, ie.
_epInteriorVectorPtr->Print(std::cout);
still shows the old values.
For now, I have simply created a method to explicitly write data from v
back into _epVectorPtr, which then shows up correctly in the view,
_epInteriorVectorPtr.
Is there a more elegant way to do assignment (or the problem in
general), so that I am not reimplementing vector operations in that
not-so-unlikely case that more flexibility from the data holder managing
the vectors is necessary?
Thanks in advance,
Robert
--
"The mind is not a vessel to be filled but a fire to be kindled."
-Plutarch
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Robert Crockett, Ph.D. Research Scientist, Tech-X Corporation
rkcrockett at txcorp.com 5621 Arapahoe Avenue, Suite A
303/996-2037 Boulder, CO 80303
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