SRC/zlantp.f(3)

💖 NAME 💖

SRC/zlantp.f — yup, that's this page, from the Library Functions Manual, and it's all about the zlantp function, bestie. 💅

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✨ SYNOPSIS ✨

🧚 Functions/Subroutines 🧚

• double precision function zlantp (norm, uplo, diag, n, ap, work) — ZLANTP returns the value of the 1-norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a triangular matrix supplied in packed form. No cap. 🦋

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🌸 Function/Subroutine Documentation 🌸

🎀 zlantp — main character energy 🎀

double precision function zlantp (character norm, character uplo, character
    diag, integer n, complex*16, dimension( * ) ap, double precision,
    dimension( * ) work)

ZLANTP returns the value of the 1-norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a triangular matrix supplied in packed form. It's giving math icon, honestly. ✨

💅 Purpose

Okay so ZLANTP returns the value of the one norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a triangular matrix A, supplied in packed form. That's the whole vibe. 🫶

🔥 Returns

ZLANTP comes back as:

!>
!>    ZLANTP = ( max(abs(A(i,j))), NORM = 'M' or 'm'
!>             (
!>             ( norm1(A),         NORM = '1', 'O' or 'o'
!>             (
!>             ( normI(A),         NORM = 'I' or 'i'
!>             (
!>             ( normF(A),         NORM = 'F', 'f', 'E' or 'e'
!>
!> where  norm1  denotes the  one norm of a matrix (maximum column sum),
!> normI  denotes the  infinity norm  of a matrix  (maximum row sum) and
!> normF  denotes the  Frobenius norm of a matrix (square root of sum of
!> squares).  Note that  max(abs(A(i,j)))  is not a consistent matrix norm.
!>

🍓 Parameters

• NORM — CHARACTER*1. Specifies the value to be returned in ZLANTP as described above. 👑
• UPLO — CHARACTER*1. Specifies whether the matrix A is upper or lower triangular.
  • = 'U': Upper triangular
  • = 'L': Lower triangular
• DIAG — CHARACTER*1. Specifies whether or not the matrix A is unit triangular.
  • = 'N': Non-unit triangular
  • = 'U': Unit triangular
• N — INTEGER. The order of the matrix A. N >= 0. When N = 0, ZLANTP is set to zero. 🧚
• AP — COMPLEX*16 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)*(2n-j)/2) = A(i,j) for j<=i<=n.

Heads up: when DIAG = 'U', the elements of the array AP corresponding to the diagonal elements of the matrix A are not referenced, but are assumed to be one. 🎀

• WORK — DOUBLE PRECISION array, dimension (MAX(1,LWORK)), where LWORK >= N when NORM = 'I'; otherwise, WORK is not referenced. 💀

👑 Author

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

⭐ Definition at line 124 of file zlantp.f.

Definition at line 124 of file zlantp.f.

🪄 Author (auto-generated)

Generated automatically by Doxygen for LAPACK from the source code.

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byeee 💖 this page is LAPACK Version 3.12.0 — SRC/zlantp.f(3) ✨🎀🦋