| <para> |
| The relational functions <function>isequal</function>, <function>isgreater</function>, |
| <function>isgreaterequal</function>, <function>isless</function>, |
| <function>islessequal</function>, and <function>islessgreater</function> always return |
| 0 if either argument is not a number (NaN). <function>isnotequal</function> returns 1 |
| if one or both arguments are not a number (NaN) and the argument type is a scalar and |
| returns -1 if one or both arguments are not a number (NaN) and the argument type is a vector. |
| </para> |
| <!-- 13-Oct-2011 --> |
