NaN: what changed
Revision 0 to 1. Removed lines have a minus sign; added lines have a plus sign.
Title: NaN
| Old | New | Line | |
|---|---|---|---|
| 1 | + | `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. | |
| 2 | + | ||
| 3 | + | ``` pascal | |
| 4 | + | program NotANumber(input, output, stderr); | |
| 5 | + | begin | |
| 6 | + | // writes 'Nan' (with spacing) on its own line | |
| 7 | + | writeLn(0/0); | |
| 8 | + | end. | |
| 9 | + | ``` | |
| 10 | + | ||
| 11 | + | Note, `NaN` exists only in the context of floating point number calculations: `0 div 0` ([[Div|integer division]]) is not allowed, though. | |
| 12 | + | ||
| 13 | + | ## See also | |
| 14 | + | ||
| 15 | + | - [Value “is not a number”](https://www.freepascal.org/docs-html/rtl/math/nan.html) | |
| 16 | + | - [`IsNan`](https://www.freepascal.org/docs-html/rtl/math/isnan.html) checks whether value is “not a number”. | |
| 17 | + | - [[TAChart documentation|TAChart documentation, § “skipping source items”]] | |
| 18 | + | ||
| 19 | + | --- | |
| 20 | + | *From the Free Pascal wiki, page "NaN", as it stood on 2022-08-06 after a change by Kai Burghardt, out of the wiki's dump of 2024-05-26. Copyright stays with the author who wrote it, according to the old wiki's [[Licensing]] page. If you have concerns about this material, [message the admin](/wiki-contact).* |