MaplePrimes - answers and comments on Question, Additional Statements in Procedures

'else'

Axel Vogt — Wed, 20 Feb 2013 02:44:03 Z

You may want to use 'else' as last statement. I even type it always before writing 'end if' in any case - before filling the body, just as a frame.

For clarity I prefer a 'return' in the if-branches (not needed), it depends on the 'language' you use and not all programming languages behave the same way on constructions.

Are you sure that's the exact procedure

Carl Love — Wed, 20 Feb 2013 05:01:19 Z

Are you sure that what you posted is an exact cut-and-paste of your procedure and its execution? In particular I don't understand how your parameter declarations

Marks:=proc(m::nonnegative, numeric)

could result in this exact error message:

Error, invalid input: Marks expects its 1st argument, m, to be of type

nonnegative and numeric, but received One

Print vs return

Joe Riel — Wed, 20 Feb 2013 06:07:19 Z

To clarify Axel's comment. The code shown uses print, which means the value is printed but nothing (NULL, actually) is returned. Beginning Maple programmers frequently use print, rather than return. Printing has its uses, but for most things, returning the computed values is better in that it allows you do something with them, rather than just inspecting them.