NaN

│ English (en) │ suomi (fi) │ русский (ru) │

NaN (not a number) is a numeric data type value representing an undefined or unrepresentable value. These values result from operations which have undefined numerical results. NaN is not the same as infinity.

0program NotANumber(input, output, stderr);
1begin
2	// writes 'Nan' (with spacing) on its own line
3	writeLn(0/0);
4end.

Note, NaN exists only in the context of floating point number calculations: 0 div 0 (integer division) is not allowed, though.

See also

• Value “is not a number”
• IsNan checks whether value is “not a number”.
• TAChart documentation, § “skipping source items”