# Routine Naming Conventions

To call each routine from the Fortran 77 program, you can use the LAPACK name.

LAPACK names are listed in Table “Computational Routines for Systems of Equations with Real Matrices” and Table “Computational Routines for Systems of Equations with Complex Matrices”, and have the structure ?yyzzz or ?yyzz, which is described below.

The initial symbol ? indicates the data type:

s

  real, single precision

c

  complex, single precision

d

  real, double precision

z

  complex, double precision

The second and third letters yy indicate the matrix type and storage scheme:

ge

  general

gb

  general band

gt

  general tridiagonal

po

  symmetric or Hermitian positive-definite

pp

  symmetric or Hermitian positive-definite (packed storage)

pb

  symmetric or Hermitian positive-definite band

pt

  symmetric or Hermitian positive-definite tridiagonal

sy

  symmetric indefinite

sp

  symmetric indefinite (packed storage)

he

  Hermitian indefinite

hp

  Hermitian indefinite (packed storage)

tr

  triangular

tp

  triangular (packed storage)

tb

  triangular band

For computational routines, the last three letters zzz indicate the computation performed:

trf

  form a triangular matrix factorization

trs

  solve the linear system with a factored matrix

con

  estimate the matrix condition number

rfs

  refine the solution and compute error bounds

tri

  compute the inverse matrix using the factorization

equ

  equilibrate a matrix.

For example, the sgetrf routine performs the triangular factorization of general real matrices in single precision; the corresponding routine for complex matrices is cgetrf.

For driver routines, the names can end with -sv (meaning a simple driver), or with -svx (meaning an expert driver).

Names of the LAPACK computational and driver routines for Fortran 95 interface in Intel MKL are the same as Fortran 77 names but without the first letter that indicates the data type. For example, the name of the routine that performs triangular factorization of general real matrices in Fortran 95 interface is getrf. Different data types are handled through defining a specific internal parameter that refers to a module block with named constants for single and double precision.

Parent topic: LAPACK Routines: Linear Equations