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Data Structures

In this chapter we illustrate the data structures used for definition of routines interfaces. They include data structures for sparse matrices, communication descriptors and preconditioners.

All the data types and the basic subroutine interfaces are defined in the module psb_base_mod; this will have to be included by every user subroutine that makes use of the library.

Real and complex data types are parametrized with a kind type defined in the library as follows:

Kind parameter for short precision real and complex data; corresponds to a REAL declaration and is normally 4 bytes.
Kind parameter for long precision real and complex data; corresponds to a DOUBLE PRECISION declaration and is normally 8 bytes.
Moreover, the library defines a long integer kind psb_long_int_k_ which normally corresponds to 64-bit integers; it is only used for the psb_sizeof utility.