/prog/ - Please explain NaN to me

Name: ELI5 2020-11-22 19:22

Without using (((abstract))) bullshite

Name: Anonymous 2020-11-22 19:37

Not a poast

Name: Anonymous 2020-11-22 20:23

>>2
Ghghhhghhhhghhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhggggggggggggggggggggggggggmmmmmmmmgh
PUMBLENUTS

Name: RedCloan 2020-11-22 20:24

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Name: Anonymous 2020-11-22 20:27

>>1
pointers have NULL,with special address of 0 indicating that pointer
is invalid/null/etc and function checks for them
floats have NaNs, with special values indicating that number is invalid/null/not initialized and functions checks for them

Name: Anonymous 2020-11-23 6:45

>>5
Why not just reuse null? Why add another magic constant?

Name: Anonymous 2020-11-23 7:07

>>6
NULLs are actually a hack to represent a NaN in pointer integers,
because 0 is a valid integer, but pointer 0 is always occupied
by interrupt table/bios rom so dereferencing address 0 is forbidden.
https://en.wikipedia.org/wiki/NaN#Integer_NaN

Name: Anonymous 2020-11-23 9:27

placeholder for nothingness

Please explain NaN to me

1 Name: ELI5 2020-11-22 19:22

2 Name: Anonymous 2020-11-22 19:37

3 Name: Anonymous 2020-11-22 20:23

4 Name: RedCloan 2020-11-22 20:24

5 Name: Anonymous 2020-11-22 20:27

6 Name: Anonymous 2020-11-23 6:45

7 Name: Anonymous 2020-11-23 7:07

8 Name: Anonymous 2020-11-23 9:27