zhpevx example program

This example finds the eigenvalues in the half-open interval

$(- 2, 2]$ , and the corresponding eigenvectors, of the Hermitian matrix

$A = (\begin{array}{l} 1 & 2 - i & 3 - i & 4 - i \\ 2 + i & 2 & 3 - 2 i & 4 - 2 i \\ 3 + i & 3 + 2 i & 3 & 4 - 3 i \\ 4 + i & 4 + 2 i & 4 + 3 i & 4 \end{array}) .$

Example program for zhpevx