code speed moving from fortran 77 compiler to f2003 compiler
in [Fortran]
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From: mecej4 on 25 Jun 2010 20:49 Lynn McGuire wrote: <...> > My long term goal is to convert our F77 code to C++ using FOR_C. > We may be trying this later this year when all of our Hollerith > code is gone. A couple of points to quote in that regard: i) Cobalt-Blue's FOR_C is an F77 to C (NOT C++) converter. ii) FOR_C may choke on many of the non-standard F77 extensions used in your code. -- mecej4
From: Lynn McGuire on 25 Jun 2010 21:03 >> My long term goal is to convert our F77 code to C++ using FOR_C. >> We may be trying this later this year when all of our Hollerith >> code is gone. > A couple of points to quote in that regard: > > i) Cobalt-Blue's FOR_C is an F77 to C (NOT C++) converter. Yes. But converting C code to C++ code is fairly easy. I've done it several times now. However, converting char * strings to STL strings is non-trivial but that can be done later. > ii) FOR_C may choke on many of the non-standard F77 extensions used in > your code. Nope. FOR_C understands the vax structure, union, map and record keywords. That is the only extension that we are currently using. Thanks, Lynn
From: Lynn McGuire on 25 Jun 2010 21:10 > Les Hatton (he has a web site) has published reports on studies of production > codes in oil exploration. C, C++ and Fortran with Fortran causing least > problems. Various others have reported that C++ is a real bear with > two caveats 1. no use of object inheritance 2. serious objects only > when objects are very well designed such as the (many-ith iteration) > of a design such as windows and the design is now static and widely used. > Basically C++ is impossible to read/maintain is there is any serious > local use of objects as one no longer knows what the code is doing with > only a local inspection. I found it here. http://www.leshatton.org/ with a specific 1992 paper at http://www.leshatton.org/Documents/JSX_0192.pdf . A lot has changed in fortran and C++ since then. I will take a look but we have quite a bit of experience here. Thanks, lynn
From: e p chandler on 25 Jun 2010 21:13 "Lynn McGuire" <lmc(a)winsim.com> wrote in message news:i02jfd$lmu$1(a)news.eternal-september.org... >>> had one of my guys add an isothermal flash cache to our general >>> flash. ... >> >> In a quick moment before heading to fields... >> >> I have no clue what you just said??? > > Our software has a large thermodynamic calculation engine built > into it. An isothermal flash is performed at a given temperature > and a given pressure. Given a certain amount of components in a > mixture (water, methane, ethane, propane, butane, pentane, carbon > dioxide, hydrogen sulfide, etc - up to 1,000 components), we will > calculate how much of each component is in the vapor phase, the > hydrocarbon liquid phase and the aqueous liquid phase. > > So anyway, we save the results of the calculations now. If the > flowsheet wants to make the same exact calculation again, we already > have it saved. Apparently saves a lot of time ! > > Thanks, > Lynn supposedly Terje Mathisen once said "All programming is an exercise in caching."
From: e p chandler on 25 Jun 2010 21:16
"mecej4" <mecej4.nyetspam(a)operamail.com> wrote in message news:i03iq8$har$1(a)news.eternal-september.org... > Lynn McGuire wrote: > > <...> >> My long term goal is to convert our F77 code to C++ using FOR_C. >> We may be trying this later this year when all of our Hollerith >> code is gone. > A couple of points to quote in that regard: > > i) Cobalt-Blue's FOR_C is an F77 to C (NOT C++) converter. > > ii) FOR_C may choke on many of the non-standard F77 extensions used in > your code. > > -- mecej4 What about the quality of the converted code? Can you read it? Can you maintain it? Or is it guacamole? |