The IEEE representation of `Not-a-Number', used when an
operation has an undefined result (e.g. 0/0). All logical operations
involving NaN return false, except for .
If you try to
plot points with the value NaN, nothing appears. This can be useful
for clipping, making holes in surfaces etc.
Condition Number :-
The condition number of a matrix (calculated
using cond) gives a fair indication of how well the matrices
can be operated upon.