Xref: utzoo comp.lang.fortran:882 comp.lang.c:11148 Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!accelerator.eng.ohio-state.edu!kaa.eng.ohio-state.edu!rob From: rob@kaa.eng.ohio-state.edu (Rob Carriere) Newsgroups: comp.lang.fortran,comp.lang.c Subject: Re: Should I convert FORTRAN code to C? Message-ID: <358@accelerator.eng.ohio-state.edu> Date: 6 Jul 88 09:01:13 GMT References: <2742@utastro.UUCP> <20008@beta.UUCP> <224@raunvis.UUCP> <750@garth.UUCP> <528@philmds.UUCP> <817@garth.UUCP> <63@cubsun.BIO.COLUMBIA.EDU> <879@garth.UUCP> Sender: news@accelerator.eng.ohio-state.edu Reply-To: rob@kaa.eng.ohio-state.edu (Rob Carriere) Organization: Ohio State Univ, College of Engineering Lines: 17 In article <879@garth.UUCP> smryan@garth.UUCP (Steven Ryan) writes: >In Algorithmic Language and Program Development, Bauer and Wossner, they cite >Paterson and Hewitt as proving, essentially, recursion is more powerful than >iteration. > I don't know the learned gentlemen, but it is certainly true that for anything that can run on a computer, recursion is *at most* as strong as iteration. Proof: the CPU is an iterative device, not a recursive one (it iterates through its' microcode or eqv) and it can excecute your program. Since a computer with unbounded memory is as strong as a Universal Turing machine, I have this nagging feeling that the proof of P&H was intended for a much more restricted environment than either B&W or the poster are (is) assuming. If I'm wrong, *do* tell me, this sounds interesting. Rob Carriere "He iterated until he had no recourse but to recurse his fate."