function blas1_d_test06 ( ) %*****************************************************************************80 % %% TEST06 demonstrates DNRM2. % % Licensing: % % This code is distributed under the GNU LGPL license. % % Modified: % % 09 May 2006 % % Author: % % John Burkardt % n = 5; lda = n + 5; % % These parameters illustrate the fact that matrices are typically % dimensioned with more space than the user requires. % fprintf ( 1, '\n' ); fprintf ( 1, 'TEST06\n' ); fprintf ( 1, ' DNRM2 computes the Euclidean norm of a vector.\n' ); fprintf ( 1, '\n' ); % % Compute the euclidean norm of a vector: % for i = 1 : n x(i) = i; end fprintf ( 1, '\n' ); fprintf ( 1, ' The vector X:\n' ); fprintf ( 1, '\n' ); for i = 1 : n fprintf ( 1, ' %6d %12f\n', i, x(i) ); end incx = 1; fprintf ( 1, '\n' ); fprintf ( 1, ' The 2-norm of X is %f\n', dnrm2 ( n, x, incx ) ); % % Compute the euclidean norm of a row or column of a matrix: % a = zeros ( lda, lda ); for i = 1 : n for j = 1 : n a(i,j) = i + j; end end incx = lda; sum1 = dnrm2 ( n, a(2,1:n), 1 ); fprintf ( 1, '\n' ); fprintf ( 1, ' The 2-norm of row 2 of A is %f\n', sum1 ); incx = 1; sum1 = dnrm2 ( n, a(1:n,2), incx ); fprintf ( 1, '\n' ); fprintf ( 1, ' The 2-norm of column 2 of A is %f\n', sum1 ); return end