aux_blas(3)

📦
version 3.11.0 · 2 versions
, in debian bookworm

🌸 NAME 🌸

aux_blas — Auxiliary BLAS, aka the little helper squad of LAPACK 💖 (this page ships with the LAPACK manual, section 3)

🎀 SYNOPSIS 🎀

✨ Functions ✨

  • integer function icamax (N, CX, INCX) — ICAMAX
  • integer function idamax (N, DX, INCX) — IDAMAX
  • integer function isamax (N, SX, INCX) — ISAMAX
  • integer function izamax (N, ZX, INCX) — IZAMAX
  • logical function lsame (CA, CB) — LSAME
  • subroutine xerbla (SRNAME, INFO) — XERBLA
  • subroutine xerbla_array (SRNAME_ARRAY, SRNAME_LEN, INFO) — XERBLA_ARRAY

💫 Detailed Description 💫

okay so bestie, this is the whole group of Auxiliary 3 BLAS routines. that's it, that's the vibe. these are the backstage crew that make the main character routines possible 🫶

🔥 Function Documentation 🔥

💅 integer function icamax (integer N, complex, dimension(*) CX, integer INCX)

ICAMAX

✨ Purpose ✨

ICAMAX finds the index of the first element having maximum |Re(.)| + |Im(.)| — like, the element with the biggest real-plus-imaginary magnitude, and she gives you the first one if there's a tie. no cap.

🎯 Parameters

  • N
    • N is INTEGER
    • number of elements in input vector(s)
  • CX
    • CX is COMPLEX array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
  • INCX
    • INCX is INTEGER
    • storage spacing between elements of CX

👑 Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

📜 Further Details:

jack dongarra, linpack, 3/11/78.
modified 3/93 to return if incx .le. 0.
modified 12/3/93, array(1) declarations changed to array(*)

🦋 integer function idamax (integer N, double precision, dimension(*) DX, integer INCX)

IDAMAX

✨ Purpose ✨

IDAMAX finds the index of the first element having maximum absolute value. first one wins, always 💖

🎯 Parameters

  • N
    • N is INTEGER
    • number of elements in input vector(s)
  • DX
    • DX is DOUBLE PRECISION array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
  • INCX
    • INCX is INTEGER
    • storage spacing between elements of DX

👑 Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

📜 Further Details:

jack dongarra, linpack, 3/11/78.
modified 3/93 to return if incx .le. 0.
modified 12/3/93, array(1) declarations changed to array(*)

🌈 integer function isamax (integer N, real, dimension(*) SX, integer INCX)

ISAMAX

✨ Purpose ✨

ISAMAX finds the index of the first element having maximum absolute value. same energy as her double-precision sister, just single precision 💅

🎯 Parameters

  • N
    • N is INTEGER
    • number of elements in input vector(s)
  • SX
    • SX is REAL array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
  • INCX
    • INCX is INTEGER
    • storage spacing between elements of SX

👑 Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

📜 Further Details:

jack dongarra, linpack, 3/11/78.
modified 3/93 to return if incx .le. 0.
modified 12/3/93, array(1) declarations changed to array(*)

🧚 integer function izamax (integer N, complex*16, dimension(*) ZX, integer INCX)

IZAMAX

✨ Purpose ✨

IZAMAX finds the index of the first element having maximum |Re(.)| + |Im(.)| — double-complex edition, she's serving the same as ICAMAX but fancier ✨

🎯 Parameters

  • N
    • N is INTEGER
    • number of elements in input vector(s)
  • ZX
    • ZX is COMPLEX*16 array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
  • INCX
    • INCX is INTEGER
    • storage spacing between elements of ZX

👑 Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

📜 Further Details:

jack dongarra, 1/15/85.
modified 3/93 to return if incx .le. 0.
modified 12/3/93, array(1) declarations changed to array(*)

🍓 logical function lsame (character CA, character CB)

LSAME

✨ Purpose ✨

LSAME returns .TRUE. if CA is the same letter as CB regardless of case. she does not care about your caps lock situation, she is above it 😌

🎯 Parameters

  • CA
    • CA is CHARACTER*1
  • CB
    • CB is CHARACTER*1
    • CA and CB specify the single characters to be compared.

👑 Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

💀 subroutine xerbla (character*(*) SRNAME, integer INFO)

XERBLA

✨ Purpose ✨

XERBLA is an error handler for the LAPACK routines. she gets called by a LAPACK routine when an input parameter has an invalid value. a message is printed and execution stops. like, dead stop. 💀

Installers may consider modifying the STOP statement in order to call system-specific exception-handling facilities.

bestie if you're an installer, this is your moment — the STOP statement is the thing you'd tweak. do with that what you will 🙈

🎯 Parameters

  • SRNAME
    • SRNAME is CHARACTER*(*)
    • The name of the routine which called XERBLA.
  • INFO
    • INFO is INTEGER
    • The position of the invalid parameter in the parameter list of the calling routine.

👑 Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

💜 subroutine xerbla_array (character(1), dimension(srname_len) SRNAME_ARRAY, integer SRNAME_LEN, integer INFO)

XERBLA_ARRAY

✨ Purpose ✨

XERBLA_ARRAY assists other languages in calling XERBLA, the LAPACK and BLAS error handler. Rather than taking a Fortran string argument as the function's name, XERBLA_ARRAY takes an array of single characters along with the array's length. XERBLA_ARRAY then copies up to 32 characters of that array into a Fortran string and passes that to XERBLA. If called with a non-positive SRNAME_LEN, XERBLA_ARRAY will call XERBLA with a string of all blank characters.

Say some macro or other device makes XERBLA_ARRAY available to C99 by a name lapack_xerbla and with a common Fortran calling convention. Then a C99 program could invoke XERBLA via:

{
  int flen = strlen(__func__);
  lapack_xerbla(__func__, &flen, &info);
}

Providing XERBLA_ARRAY is not necessary for intercepting LAPACK errors. XERBLA_ARRAY calls XERBLA.

🎯 Parameters

  • SRNAME_ARRAY
    • SRNAME_ARRAY is CHARACTER(1) array, dimension (SRNAME_LEN)
    • The name of the routine which called XERBLA_ARRAY.
  • SRNAME_LEN
    • SRNAME_LEN is INTEGER
    • The length of the name in SRNAME_ARRAY.
  • INFO
    • INFO is INTEGER
    • The position of the invalid parameter in the parameter list of the calling routine.

👑 Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

🫶 Author 🫶

Generated automatically by Doxygen for LAPACK from the source code.

okay that's the whole page bestie, you ate 💅✨ this was aux_blas(3) from LAPACK Version 3.11.0, dated Sun Nov 27 2022. go forth and slay your BLAS calls 🎀🦋

📦 where this page comes from