kcby@fenix.Atlanta.NCR.COM (kcby) (05/23/88)
We are planning to use c++ to implement an object oriented design. Since this is our first use of both c++ and the OO approach, I have no idea how to answer the usual questions of "How much memory will the system take?", "How long will it take to code (i.e. how many lines of code will be required?)" and "How fast will it run?" It seems to me that there are certain aspects of the design which must be worked out before estimating any of these: what classes will be needed and what messages must each of these classes support? Then to work out memory and coding time, some kind of inheritance structure must be assumed, to determine how much reuse will occur. And a guess must be made as to how many lines of code will be required for each message (either individually, or in general). Finally, to estimate how fast it will run, it seems that you need to know the particular objects which will implement a given operation, and what messages must flow between them to accomplish the activity, as well as how many lines of code each message will require. And, some kind of approximation will be required regarding c++ source to native translation for memory and speed estimates. Since none of this information is available early in the design process, and since approximations on source to native size/speed require previous implementations to look at, I wonder what alternatives might be used for "guesstimating" size, coding time and performance for a first time OO/c++ implementation. For example, could it be done by figuring what it would take doing a standard structured approach using C, and then applying some factors to figure size, LOC and performance? Or would I be better off making wild swags at the figures for the information needed to estimate an OO design? Can anyone suggest an approach which they used? Did you over or under estimate based on that approach? If so, by how much? K.C. Burgess Yakemovic "Some of my best friends are mammals." kcby@Atlanta.NCR.com - Robert T. Bakker, author The Dinosaur Heresies -- K.C. Burgess Yakemovic "Some of my best friends are mammals." kcby@Atlanta.NCR.com - Robert T. Bakker, author The Dinosaur Heresies