Usefulness of signaling NaN?

Question

I\'ve recently read up quite a bit on IEEE 754 and the x87 architecture. I was thinking of using NaN as a \"missing value\" in some numeric calculation code I\'m working on

Answer 1

Couldn't you just have a const uint64_t where the bits have been set to those of a signaling nan? as long as you treat it as an integer type, the signaling nan is not different from other integers. You could write it where you want through pointer-casting:

Const uint64_t sNan = 0xfff0000000000000;
Double[] myData;
...
Uint64* copier = (uint64_t*) &myData[index];
*copier=sNan | myErrorFlags;

For info on the bits to set: https://www.doc.ic.ac.uk/~eedwards/compsys/float/nan.html