Indicates the locations (rows and columns) in the matrix where nonzeros will be inserted using a local number of the rows and columns


PetscErrorCode MatPreallocateSet(PetscInt nrows, PetscInt *rows,PetscInt ncols, PetscInt *cols,PetscInt *dnz, PetscInt *onz)
Not Collective

Input Parameters

row - the row
ncols - the number of columns in the matrix
cols - the columns indicated

Output Parameters

dnz - the array that will be passed to the matrix preallocation routines
ozn - the other array passed to the matrix preallocation routines


See the chapter in the users manual on performance for more details

Do not malloc or free dnz and onz that is handled internally by these routines

See Also

MatPreallocateFinalize(), MatPreallocateSet(), MatPreallocateSymmetricSet(), MatPreallocateInitialize(),
MatPreallocateInitialize(), MatPreallocateSymmetricSetLocal(), MatPreallocateSetLocal()

Index of all Mat routines
Table of Contents for all manual pages
Index of all manual pages