Jean-Claude Wippler wrote: [relational notation] > A vector (sequence) is: #:R1,R2,...,RM > A set is: K1,K2,...KN: > A multi-set is: K1,K2,...KN,#: > A map is: K1,K2,...KN:#,R1,R2,...,RM > A multi-map is: K1,K2,...KN,#:R1,R2,...,RM This is a nice classification! To my understanding, why not A map is: K1,K2,...KN:R1,R2,...,RM Where is a # in a map? And what do you mean by N and M? Is K1..KN one key, mae up of N sub keys, or do you mean the whole set of keys, where each one is mapped somehow. I guess not, the notation looks like I should think of tuples. No, that would imply that N and M were fixed, but they are not. But you say "- collections consist of objects, each of them with attributes". Ok, N and M seem to be individual for each object, right? But when defining a map for instance, and we're talking of the objects, then the map is the set of these objects, and I have to think of K[0]..K(N(o)):R[0]..R(M(o)) where N and M are functions of the individual object o, right? Isn't it then better to think different of these objects, saying they can produce some key object and some value object of any shape, and a position, where each of these can be missing? ciao - chris -- Christian Tismer :^) <mailto:tismer@appliedbiometrics.com> Applied Biometrics GmbH : Have a break! Take a ride on Python's Kaunstr. 26 : *Starship* http://starship.python.net 14163 Berlin : PGP key -> http://wwwkeys.pgp.net PGP Fingerprint E182 71C7 1A9D 66E9 9D15 D3CC D4D7 93E2 1FAE F6DF we're tired of banana software - shipped green, ripens at home
RetroSearch is an open source project built by @garambo | Open a GitHub Issue
Search and Browse the WWW like it's 1997 | Search results from DuckDuckGo
HTML:
3.2
| Encoding:
UTF-8
| Version:
0.7.4