Hi Jeff, Thank you very much your responses, I am sorry I didn't understand your answer because I dont know what does it mean f,g and h. But I want to get this structure and later I have to get by the 3rd column decreasing order in this structure. And than I can use 1 st and 2nd columns together. Another concepts composite type i dont understand.
regards Kenan 29 Kasım 2014 Cumartesi 17:09:27 UTC-5 tarihinde Jeff Waller yazdı: > > >> This 3 column are neccessary for later analysis in my work, first and >> second column index and 3rd values. I have to use three columns same time. >> > > Ok right so, whatever the exact expression is, it's going to have the form > > f(A[:,1:2]) > > where f does some indexing function followed sometime later by > > g(A[:,3]) > > where g does some value stuff. > > but you don't have > > h(A[:,1:3]) > > because there's no builtin thing that does both indexing and evaluation > simultaneously > I'm using f g and h just to short-hand describe what's going on, not to > imply > they are actually called f, g, h or even that they're actually formally > functions. So if that's > the case then really why not use A and B? Convenience, Encapsulation? > Sure, that's valid > but I'm suggesting that those two things are even better served by using > composites, because > then you have the type system working for you instead of against you. >