hb_read -- Read a sparse matrix from a file in the Harwell-Boeing format

Type:

Asynchronous.

On Entry

filename

The name of the file to be read.
Type:optional.
Specified as: a character variable containing a valid file name, or -, in which case the default input unit 5 (i.e. standard input in Unix jargon) is used. Default: -.

iunit

The Fortran file unit number.
Type:optional.
Specified as: an integer value. Only meaningful if filename is not -.

On Return

a

the sparse matrix read from file.
Type:required.
Specified as: a structured data of type spdatapsb_Tspmat_type.

b

Rigth hand side(s).
Type: Optional
An array of type real or complex, rank 2 and having the ALLOCATABLE attribute; will be allocated and filled in if the input file contains a right hand side, otherwise will be left in the UNALLOCATED state.

mtitle

Matrix title.
Type: Optional
A charachter variable of length 72 holding a copy of the matrix title as specified by the Harwell-Boeing format and contained in the input file.

iret

Error code.
Type: required
An integer value; 0 means no error has been detected.