Example 2 (from Program LA_PBSV_EXAMPLE)

The results below are computed with $\epsilon = 1.19209 \times 10^{-7}$.

$$A = \left( \begin{array}{rrrrrrr} 16 & 3 & 2 & 1 \\ 3 & ... ...& 111 \\ 31 & 62 & 93 \\ 22 & 44 & 66 \end{array} \right).$$

AB and B on entry:

$$\begin{array}{c} {\bf AB} \\ \begin{array}{\vert rrrrrrr\... ...& 62 & 93 \\ 22 & 44 & 66 \\ \hline \end{array} \end{array}$$

The call:
CALL LA_PBSV( AB, B, INFO=INFO )

AB, B and INFO on exit:

$$\begin{array}{c} {\bf AB} \\ \begin{array}{\vert@{\hspace{2m... ...5.24475 & 5.05429 & 4.64073 \\ \hline \end{array} \end{array}$$

$$\begin{array}{cc} {\bf AB} \\ \begin{array}{l\vert} \hline ... ...} \hspace{0.50 cm} \begin{array}{c} {\bf INFO} = 0 \end{array}$$

Matrices $U$ and $X$, where $A\,=U^TU$ and $X$ is the solution of the system $A\,X = B$:

$$U = \left( \begin{array}{@{\hspace{1mm}}l@{\hspace{1mm}}l@{\h... ...{-1} \\ & & & & & 4.64073 \\ & & & & & \end{array} \right.$$

$$\left. \begin{array}{l} \\ \\ \\ 1.90667 \times 10^{-1... ... 3.00000 \\ 1.00000 & 2.00000 & 3.00000 \end{array} \right).$$