BLAS/SRC/ztpmv.f(3)

✨ NAME ✨

BLAS/SRC/ztpmv.f — bestie, you've found the file that does the packed triangular matrix-vector thing 💅

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🎀 SYNOPSIS 🎀

Functions/Subroutines

subroutine ztpmv (uplo, trans, diag, n, ap, x, incx)
    ZTPMV

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🦋 Function/Subroutine Documentation 🦋

subroutine ztpmv (character uplo, character trans, character diag, integer
    n, complex*16, dimension(*) ap, complex*16, dimension(*) x, integer
    incx)
    ZTPMV

🌸 Purpose 🌸

okay so ZTPMV performs one of the matrix-vector operations

x := A*x,   or   x := A**T*x,   or   x := A**H*x,

where x is an n element vector and A is an n by n unit, or non-unit, upper or lower triangular matrix, supplied in packed form. no cap, that's literally the whole vibe 🔥

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💖 Parameters 💖

• UPLO — UPLO is CHARACTER*1. On entry, UPLO specifies whether the matrix is an upper or lower triangular matrix as follows:
  • UPLO = 'U' or 'u' — A is an upper triangular matrix. 👑
  • UPLO = 'L' or 'l' — A is a lower triangular matrix. 🫶
• TRANS — TRANS is CHARACTER*1. On entry, TRANS specifies the operation to be performed as follows:
  • TRANS = 'N' or 'n' — x := A*x. ✨
  • TRANS = 'T' or 't' — x := A**T*x. 💫
  • TRANS = 'C' or 'c' — x := A**H*x. 🌀
• DIAG — DIAG is CHARACTER*1. On entry, DIAG specifies whether or not A is unit triangular as follows:
  • DIAG = 'U' or 'u' — A is assumed to be unit triangular. 🎀
  • DIAG = 'N' or 'n' — A is not assumed to be unit triangular. 🙈
• N — N is INTEGER. On entry, N specifies the order of the matrix A. N must be at least zero. (yes bestie, zero is allowed, we love a chill minimum 💅)
• AP — AP is COMPLEX*16 array, dimension at least ( ( n*( n + 1 ) )/2 ). Before entry with UPLO = 'U' or 'u', the array AP must contain the upper triangular matrix packed sequentially, column by column, so that AP( 1 ) contains a( 1, 1 ), AP( 2 ) and AP( 3 ) contain a( 1, 2 ) and a( 2, 2 ) respectively, and so on. Before entry with UPLO = 'L' or 'l', the array AP must contain the lower triangular matrix packed sequentially, column by column, so that AP( 1 ) contains a( 1, 1 ), AP( 2 ) and AP( 3 ) contain a( 2, 1 ) and a( 3, 1 ) respectively, and so on. Note that when DIAG = 'U' or 'u', the diagonal elements of A are not referenced, but are assumed to be unity. 🧚
• X — X is COMPLEX*16 array, dimension at least ( 1 + ( n - 1 )*abs( INCX ) ). Before entry, the incremented array X must contain the n element vector x. On exit, X is overwritten with the transformed vector x. 💀 (rip your original data, it's giving glow-up)
• INCX — INCX is INTEGER. On entry, INCX specifies the increment for the elements of X. INCX must not be zero. 🚫

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⭐ Author ⭐

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

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🌈 Further Details 🌈

Level 2 Blas routine.
The vector and matrix arguments are not referenced when N = 0, or M = 0

-- Written on 22-October-1986.
   Jack Dongarra, Argonne National Lab.
   Jeremy Du Croz, Nag Central Office.
   Sven Hammarling, Nag Central Office.
   Richard Hanson, Sandia National Labs.

Definition at line 141 of file ztpmv.f. 👑

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💜 Author 💜

Generated automatically by Doxygen for LAPACK from the source code.

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and that's the whole page bestie, we ate and left no crumbs 🍓✨ — this was Version 3.12.0, dated Tue Nov 28 2023 12:08:41, straight from BLAS/SRC/ztpmv.f(3). periodt. 💖