next up previous contents
Next: Scaled Vector (Object) Addition Up: Scaling a Vector (Object) Previous: PLAPACK FORTRAN-C interface

PLAPACK calls

The PLAPACK calling sequences for scaling an object are place HR here

figure6423

figure6427

figure6430

place HR here The data type of the operands and parameters like vector length and stride are now passed as part of linear algebra objects alpha and x.

Local call:

When a node calls PLA_Local_scal, the operation is equivalent to extracting the local information (data type, length, and pointer to the buffers) and locally performing the scaling. The object type can by any valid PLAPACK object type: The local scale operation can also be used to scale two dimensional objects (multiscalars, (projected) (duplicated) multivectors and matrices). The local dimensions of alpha must be tex2html_wrap_inline13791 , but it can be of any object type. All objects must have the same data type. Notice: no communication is performed as part of this call. Thus, all information must be locally available.

Global call:

All nodes must simultaneously call PLA_Swap, which performs the BLAS call on the distributed objects. Parameter alpha must be a tex2html_wrap_inline13793 multiscalar. Parameter x can be of any object type.


next up previous contents
Next: Scaled Vector (Object) Addition Up: Scaling a Vector (Object) Previous: PLAPACK FORTRAN-C interface

rvdg@cs.utexas.edu