STPTRS(3)

💅 NAME 💅

okay bestie, this is the Library Functions Manual page for stptrs.f(3) — header path is /home/abui...RC/stptrs.f(3), and the NAME entry is literally this file path:

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

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✨ SYNOPSIS ✨

🦋 Functions/Subroutines 🦋

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

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🫶 Function/Subroutine Documentation 🫶

subroutine STPTRS (character uplo, character trans, character diag, integer
     n, integer nrhs, real, dimension( * ) ap, real, dimension( ldb, * ) b,
     integer ldb, integer info)
     STPTRS

🎀 Purpose 🎀

STPTRS solves a triangular system of the form

   A * X = B  or  A**T * 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. no cap, that check matters.

🌸 Parameters 🌸

• UPLO — UPLO is CHARACTER*1; it tells you which triangle A is living in:
  • = 'U': A is upper triangular;
  • = 'L': A is lower triangular.
• TRANS — TRANS is CHARACTER*1; it specifies 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 = Transpose)
• DIAG — DIAG is CHARACTER*1; this is the unit/non-unit triangle vibe check:
  • = 'N': A is non-unit triangular;
  • = 'U': A is unit triangular.
• N — N is INTEGER; the order of the matrix A. Constraint: N >= 0.
• NRHS — NRHS is INTEGER; the number of right hand sides, i.e., the number of columns of the matrix B. Constraint: NRHS >= 0.
• AP — AP is REAL array, dimension (N*(N+1)/2); 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 — B is REAL array, dimension (LDB,NRHS); on entry, the right hand side matrix B. On exit, if INFO = 0, the solution matrix X.
• LDB — LDB is INTEGER; the leading dimension of the array B. Constraint: LDB >= max(1,N).
• INFO — INFO is INTEGER; the exit-status bestie:
  • = 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 stptrs.f.

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⭐ Author ⭐

Generated automatically by Doxygen for LAPACK from the source code.

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Later, bestie! 💖 This page says source LAPACK, Version 3.12.0, and the footer path is /home/abui...RC/stptrs.f(3). The footer date slot isn’t filled in on this copy, so I’m not inventing one — no cap, periodt. ✨