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“No division”? How do you reason this? Integer division is a thing
by instruction-ptr 9y ago
“No division”? How do you reason this? Integer division is a thing
- Avshalom 9y agodivision is not defined on the set of integers, you only have modular arithmetic.
- instruction-ptr 9y agoSee section 7 of http://www.cs.cmu.edu/~15122/handouts/02-ints.pdf http://www.cs.cmu.edu/~15122/handouts/02-ints.pdf (As an aside nearly every language defines division on the set of integers this way so it’s not even like we’re making this up)
- jameshart 9y agodivision is also not defined on the set of IEEE binary floating point numbers, you only have (well-defined) rounding. For that matter, addition and subtraction aren't defined on the range of fixed-bit-width integers.
- recursive 9y agoIt is defined and you can do it in C without using floats. On the other hand, even if you do use floats, arbitrary arithmetic is not invertible. In other words a / b * b isn't necessarily a, regardless of what types they are.
- baby 9y agoWhat do you mean division is not defined on the set of integers? Mathematically or programmatically? Because yes you have euclidean divisions which are divisions for the integers.