.TH "TESTING/LIN/dptt02.f" 3 "Version 3.12.0" "LAPACK" \" -*- nroff -*-
.ad l
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.SH NAME
TESTING/LIN/dptt02.f
.SH SYNOPSIS
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.PP
.SS "Functions/Subroutines"

.in +1c
.ti -1c
.RI "subroutine \fBdptt02\fP (n, nrhs, d, e, x, ldx, b, ldb, resid)"
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.RI "\fBDPTT02\fP "
.in -1c
.SH "Function/Subroutine Documentation"
.PP 
.SS "subroutine dptt02 (integer n, integer nrhs, double precision, dimension( * ) d, double precision, dimension( * ) e, double precision, dimension( ldx, * ) x, integer ldx, double precision, dimension( ldb, * ) b, integer ldb, double precision resid)"

.PP
\fBDPTT02\fP 
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\fBPurpose:\fP
.RS 4

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.nf
 DPTT02 computes the residual for the solution to a symmetric
 tridiagonal system of equations:
    RESID = norm(B - A*X) / (norm(A) * norm(X) * EPS),
 where EPS is the machine epsilon\&.
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.RE
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\fBParameters\fP
.RS 4
\fIN\fP 
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.nf
          N is INTEGER
          The order of the matrix A\&.
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.br
\fINRHS\fP 
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          NRHS is INTEGER
          The number of right hand sides, i\&.e\&., the number of columns
          of the matrices B and X\&.  NRHS >= 0\&.
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\fID\fP 
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.nf
          D is DOUBLE PRECISION array, dimension (N)
          The n diagonal elements of the tridiagonal matrix A\&.
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\fIE\fP 
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          E is DOUBLE PRECISION array, dimension (N-1)
          The (n-1) subdiagonal elements of the tridiagonal matrix A\&.
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\fIX\fP 
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          X is DOUBLE PRECISION array, dimension (LDX,NRHS)
          The n by nrhs matrix of solution vectors X\&.
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\fILDX\fP 
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          LDX is INTEGER
          The leading dimension of the array X\&.  LDX >= max(1,N)\&.
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\fIB\fP 
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          B is DOUBLE PRECISION array, dimension (LDB,NRHS)
          On entry, the n by nrhs matrix of right hand side vectors B\&.
          On exit, B is overwritten with the difference B - A*X\&.
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\fILDB\fP 
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          LDB is INTEGER
          The leading dimension of the array B\&.  LDB >= max(1,N)\&.
.fi
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.br
\fIRESID\fP 
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.nf
          RESID is DOUBLE PRECISION
          norm(B - A*X) / (norm(A) * norm(X) * EPS)
.fi
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.RE
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\fBAuthor\fP
.RS 4
Univ\&. of Tennessee 
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Univ\&. of California Berkeley 
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Univ\&. of Colorado Denver 
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NAG Ltd\&. 
.RE
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Definition at line \fB103\fP of file \fBdptt02\&.f\fP\&.
.SH "Author"
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Generated automatically by Doxygen for LAPACK from the source code\&.