# Name

**HPL_numroc**Compute the local number of row/columns.

# Synopsis

`#include "hpl.h"`

`int`

`HPL_numroc(`

`const int`

`N`

,
`const int`

`INB`

,
`const int`

`NB`

,
`const int`

`PROC`

,
`const int`

`SRCPROC`

,
`const int`

`NPROCS`

`);`

# Description

**HPL_numroc**returns the local number of matrix rows/columns process PROC will get if we give out N rows/columns starting from global index 0.

# Arguments

N (input) const int On entry, N specifies the number of rows/columns being dealt out. N must be at least zero.

INB (input) const int On entry, INB specifies the size of the first block of the global matrix. INB must be at least one.

NB (input) const int On entry, NB specifies the blocking factor used to partition and distribute the matrix A. NB must be larger than one.

PROC (input) const int On entry, PROC specifies the coordinate of the process whose local portion is determined. PROC must be at least zero and strictly less than NPROCS.

SRCPROC (input) const int On entry, SRCPROC specifies the coordinate of the process that possesses the first row or column of the matrix. SRCPROC must be at least zero and strictly less than NPROCS.

NPROCS (input) const int On entry, NPROCS specifies the total number of process rows or columns over which the matrix is distributed. NPROCS must be at least one.