ZGET03(3)

🎀 ZGET03 💅 — a LAPACK(3) moment, from the Library Functions Manual

okay bestie, so this one lives at /home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/TESTING/LIN/zget03.f and honestly? it's a vibe check for your linear algebra. no cap.

---

✨ NAME ✨

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/TESTING/LIN/zget03.f

that's the whole name, she's a whole file path, we respect her 🫶

---

🌸 SYNOPSIS 🌸

Functions/Subroutines

• subroutine ZGET03 (n, a, lda, ainv, ldainv, work, ldwork, rwork, rcond, resid) — the one and only. she's giving "let me check that inverse for you" energy.

subroutine ZGET03 (n, a, lda, ainv, ldainv, work, ldwork, rwork, rcond,
    resid)

ZGET03. that's it. that's the subroutine. 🦋

---

🧚 Function/Subroutine Documentation 🧚

subroutine ZGET03 (integer n, complex*16, dimension( lda, * ) a, integer lda, complex*16, dimension( ldainv, * ) ainv, integer ldainv, complex*16, dimension( ldwork, * ) work, integer ldwork, double precision, dimension( * ) rwork, double precision rcond, double precision resid)

ZGET03 💖

🌈 Purpose:

!>
!> ZGET03 computes the residual for a general matrix times its inverse:
!>    norm( I - AINV*A ) / ( N * norm(A) * norm(AINV) * EPS ),
!> where EPS is the machine epsilon.
!>

so basically, bestie: she multiplies your inverse by your original matrix, subtracts that from I (the identity, the main character 👑), and then normalizes the whole mess by N * norm(A) * norm(AINV) * EPS. that's the residual. that's the vibe check. and EPS is the machine epsilon, iykyk. ✨

---

🍓 Parameters 🍓

• N — N is INTEGER. the number of rows and columns of the matrix A. and like, N >= 0, obviously. no negative-size matrices, we don't do that here 🙈

!>          N is INTEGER
!>          The number of rows and columns of the matrix A.  N >= 0.
!>

• A — A is COMPLEX*16 array, dimension (LDA,N). it's literally the original N x N matrix A. the before picture 💜

!>          A is COMPLEX*16 array, dimension (LDA,N)
!>          The original N x N matrix A.
!>

• LDA — LDA is INTEGER. it's the leading dimension of the array A, and she must satisfy LDA >= max(1,N). rules are rules, bestie. 🎀

!>          LDA is INTEGER
!>          The leading dimension of the array A.  LDA >= max(1,N).
!>

• AINV — AINV is COMPLEX*16 array, dimension (LDAINV,N). this is the inverse of the matrix A. the after picture. the glow-up. ✨

!>          AINV is COMPLEX*16 array, dimension (LDAINV,N)
!>          The inverse of the matrix A.
!>

• LDAINV — LDAINV is INTEGER. leading dimension of the array AINV, and yes she also needs LDAINV >= max(1,N). consistency queen 💅

!>          LDAINV is INTEGER
!>          The leading dimension of the array AINV.  LDAINV >= max(1,N).
!>

• WORK — WORK is COMPLEX*16 array, dimension (LDWORK,N). the workspace. she's just there to do the work, no notes. 🧚

!>          WORK is COMPLEX*16 array, dimension (LDWORK,N)
!>

• LDWORK — LDWORK is INTEGER. leading dimension of the array WORK, and LDWORK >= max(1,N) — same energy as the others, fr fr.

!>          LDWORK is INTEGER
!>          The leading dimension of the array WORK.  LDWORK >= max(1,N).
!>

• RWORK — RWORK is DOUBLE PRECISION array, dimension (N). real workspace for real ones. 🫶

!>          RWORK is DOUBLE PRECISION array, dimension (N)
!>

• RCOND — RCOND is DOUBLE PRECISION. the reciprocal of the condition number of A, computed as ( 1/norm(A) ) / norm(AINV). look at her, doing the math, iconic. 🔥

!>          RCOND is DOUBLE PRECISION
!>          The reciprocal of the condition number of A, computed as
!>          ( 1/norm(A) ) / norm(AINV).
!>

• RESID — RESID is DOUBLE PRECISION. and she's literally norm(I - AINV*A) / ( N * norm(A) * norm(AINV) * EPS ). the final answer. the reveal. the moment. 👑

!>          RESID is DOUBLE PRECISION
!>          norm(I - AINV*A) / ( N * norm(A) * norm(AINV) * EPS )
!>

---

💀 Author 💀

• Univ. of Tennessee
• Univ. of California Berkeley
• Univ. of Colorado Denver
• NAG Ltd.

the whole squad, no cap. 🌈

Definition at line 108 of file zget03.f.

---

⭐ Author ⭐ (yes, again, different author section, don't come for me)

Generated automatically by Doxygen for LAPACK from the source code. she was literally born from a script, main character energy 💅✨

---

and that's the page bestie!! LAPACK, Version 3.12.0, and this whole thing comes to you from /home/abui...IN/zget03.f(3) — go forth and compute your residuals 💖🎀🦋