ZTPTRS(3)

okay bestie, welcome to the ztptrs.f(3) page — yes, from the Library Functions Manual — and no cap, this is the packed-triangular-system solver lore you didn’t know you needed. 💅✨

💖 NAME 💖

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/ztptrs.f

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✨ SYNOPSIS ✨

Here’s the group-chat receipt, bestie:

🧚 Functions/Subroutines 🧚

   subroutine ZTPTRS (uplo, trans, diag, n, nrhs, ap, b, ldb, info)
       ZTPTRS

🎀 Function/Subroutine Documentation 🎀

🦋 subroutine ZTPTRS 🦋

   subroutine ZTPTRS (character uplo, character trans, character diag, integer
       n, integer nrhs, complex*16, dimension( * ) ap, complex*16, dimension(
       ldb, * ) b, integer ldb, integer info)
       ZTPTRS

💜 Purpose 💜

Okay so ZTPTRS solves a triangular system of the form

A * X = B,  A**T * X = B,  or  A**H * X = B,

where A is a triangular matrix of order N stored in packed format, and B is an N-by-NRHS matrix. A check is made to verify that A is nonsingular. slay 💚

🌈 Parameters 🌈

• UPLO — it’s a CHARACTER*1, and it tells you which triangle is the main character:
  • = 'U': A is upper triangular;
  • = 'L': A is lower triangular.
• TRANS — CHARACTER*1, specifying the form of the system of equations:
  • = 'N': A * X = B (No transpose)
  • = 'T': A**T * X = B (Transpose)
  • = 'C': A**H * X = B (Conjugate transpose)
• DIAG — CHARACTER*1, the diagonal vibe check:
  • = 'N': A is non-unit triangular;
  • = 'U': A is unit triangular.
• N — INTEGER, the order of the matrix A. N >= 0. no negative-order nonsense, periodt 🩵
• NRHS — INTEGER, the number of right hand sides, i.e., the number of columns of the matrix B. NRHS >= 0.
• AP — COMPLEX*16 array, dimension (N*(N+1)/2). It’s the upper or lower triangular matrix A, packed columnwise in a linear array. The j-th column of A is stored in the array AP as follows:
  • if UPLO = 'U', AP(i + (j-1)*j/2) = A(i,j) for 1<=i<=j;
  • if UPLO = 'L', AP(i + (j-1)*(2*n-j)/2) = A(i,j) for j<=i<=n.
• B — COMPLEX*16 array, dimension (LDB,NRHS). On entry, the right hand side matrix B. On exit, if INFO = 0, the solution matrix X. iconic glow-up behavior ✨
• LDB — INTEGER, the leading dimension of the array B. LDB >= max(1,N).
• INFO — INTEGER, the receipts:
  • = 0: successful exit
  • < 0: if INFO = -i, the i-th argument had an illegal value
  • > 0: if INFO = i, the i-th diagonal element of A is zero, indicating that the matrix is singular and the solutions X have not been computed.

🫶 Author 🫶

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

Definition at line 129 of file ztptrs.f.

👑 Author 👑

Generated automatically by Doxygen for LAPACK from the source code.

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That’s the whole page, bestie — LAPACK Version 3.12.0, /home/abui...RC/ztptrs.f(3), and no date listed in the footer, so we’re signing off with pure cute-terminal vibes. 💖🎀