Messages from Usenet group comp.lang.idl-pvwave, compiled by Paulo Penteado
Re: Discussion on global variables in IDL - reply to Martin and Pavel
First of all I'd like to thank you for information that using COMMONs is not only not cool but could be dangerous for a life. I’ll take this into account in the future :-) I agree with you on the whole and want just clarify some items of my subjective position. The fact is that very often you don’t know exactly what you are going to get from program. And if you write in C (even more with object programming) you really have to design all data structure before writing. And it’s very tempting not to do so. And I’ve created illusion for myself that IDL allows me to just sit and program. At least I am not disappointed in this yet. If I know exactly what I’m going to do why should I use IDL. I would better write in C (for ex.) using math libraries and I get fast cheap executable program with high flexible GUI. As many do by the way. The fact that if I don’t know exactly what I’m going to do I spend five times much more time on that in comparison with IDL. And I should be much more qualified in programming. Of course, it’s right mainly for scientific data processing purpose. Once I’ve met an idea that a book on mathematics can be either exact or understandable. I seem the same is right for programming to some extent. Program in IDL is not exact but understandable. IDL implicitly takes upon itself many of the functions that I don’t want think about during data processing. I don’t need declare variables, do type conversion, write FORs to copy arrays, reserve and clear memory and so on. I can interactively run simple debug code to found out what’s happened on error. It is excellent. And I dislike when I should do something that doesn’t concern to the point of the process. I must not use pointers if I don’t use dynamic data arrays. I must not use structures if I don’t have actually structured data. And I must not use object-oriented technique if I don’t need inheritance for example. I don’t know really if I succeeded to put into words my conception but I have tried. Cheers, Dmitriy Remote Sensing Center of ISTP, Irkutsk alt@iszf.irk.ru