
class="cmtt-10x-x-109">&#8217;DIAG&#8217;</span></span></span> or
<span class="obeylines-h"><span class="verb"><span 
class="cmtt-10x-x-109">&#8217;JACOBI&#8217;</span></span></span> </td><td  style="white-space:wrap; text-align:left;" id="TBL-1-3-3"  
class="td11"><!--l. 71--><p class="noindent" >Diagonal preconditioner. For any zero diagonal
entry  of  the  matrix  to  be  preconditioned,  the
corresponding entry of the preconditioner is set
to&#x00A0;1.                                                   