I am about to start rewriting a fortran program to ansi C++.
Would it be best to convert the variables that are 'real' to float?
double? long double?
5  6029 
Al wrote: I am about to start rewriting a fortran program to ansi C++.
Step 1: use f2c, to translate Fortran source into complete C source that
compiles and runs. F2C is so stable that many use it as their Fortran
compiler. They never read the C intermediate.
Step 2: Read the C intermediate. It is not that bad, once you learn how
stereotypically it wraps all the Fortran nuances. But it won't be C++. Don't
ask it to be and you'l do fine. You can make minor tweaks to code in this
state.
Step 3: Write a billion unit tests that completely characterize this legacy
code. Many tests can pass sample data, collect sample results, and compare
them to golden references.
Step 4: Erase the source, and make each unit test pass by writing new
source.
Notice that at each step you can stop and have something useful to work
with.
--
Phlip http://www.c2.com/cgi/wiki?ZeekLand
Al wrote: I am about to start rewriting a fortran program to ansi C++.
Would it be best to convert the variables that are 'real' to float?
double? long double?
It depends on the precision that you want. I would begin with double.
--
Ioannis Vranos http://www23.brinkster.com/noicys
"Al" <al********@hot mail.com> wrote in message
news:11******** **************@ z14g2000cwz.goo glegroups.com.. . I am about to start rewriting a fortran program to ansi C++.
Would it be best to convert the variables that are 'real' to float?
double? long double?
To be on the safe side I'd go with double.
Cheers
Chris
Chris Theis wrote: "Al" <al********@hot mail.com> wrote in message
news:11******** **************@ z14g2000cwz.goo glegroups.com.. .I am about to start rewriting a fortran program to ansi C++.
Would it be best to convert the variables that are 'real' to float?
double? long double?
To be on the safe side I'd go with double.
I agree, but let me note that most Fortran compilers on 32-bit
platforms use 4-byte reals, which corresponds to a C/C++ float. If the
Fortran programmer thought 8 byte variables were necessary, he would
have declared them as DOUBLE PRECISION or the nonstandard, but common,
REAL*8. Many Fortran compilers have an option to "promote" REAL
variables to double precision. If one has a make file or build script
showing that this option was used, then the corresponding C++ variables
should be double.
Chris Theis wrote: "Al" <al********@hot mail.com> wrote in message
news:11******** **************@ z14g2000cwz.goo glegroups.com.. .
I am about to start rewriting a fortran program to ansi C++.
Would it be best to convert the variables that are 'real' to float?
double? long double?
To be on the safe side I'd go with double.
Actually, if you're lucky, then they're already declared in fortran as
either
REAL*4 or REAL*8, in which case the decision for float or double is made
for you. Otherwise, I'd agree with Chris and go with double.
It's been ages since I did FORTRAN (back in the ancient WATFOR/WATFIV
days), but didn't it also have an explicit DOUBLE PRECISION declaration? This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
by: Santosh |
last post by:
Hello all,
I am trying to interface c++ and fortran, the fortran code is already
there and I was successful
in calling the subroutines and functions, but was not able to send the
fortran module data into my C++ code and viceversa. I used gcc 3.3 and
g95 for c++ and fortran resp. Here is a little made up sample code so
that u could understand my problem.
$cat fort.f90
|
by: NM |
last post by:
Hello all,
I am supposed to do some mixed programming with c++ and fortran.
I was succeeful in exchanging the 2D arrays from fortran to c++ and the
other way, but was unable
to that same with the 3D arrays, the values passed are not all the
same. I am also pasting the fortran and c++ codes so that you could
have a look at them.
////C++ Code
|
by: Bigdakine |
last post by:
I don't know if this is the right forum for this, and if not please suggest one
which fits.
I have to call a fortran sub routine from a C main program.
The fortran subroutine statement is
wload(starttime, duration, station, component, dataray, nsamp, calib, srate,
samplength, datadir)
|
by: sam |
last post by:
Hi,
Can anyone help me find a software that can convert a code in 'C'
to 'Fortran77/90' automatically?
Thanks in advance.
Sam.
|
by: travisperkins03 |
last post by:
Hi,
I have read somewhere that C code sometimes cannot be compiled to be as
efficient as FORTRAN, eg for matrix multiplication, because a C
compiler cannot make the assumptions about arrays that a FORTRAN
compiler can. But I don't understand the example, not least because I
don't understand FORTRAN. I also don't understand why it is more
efficient in this case for a compiler to choose the order of evaluation
(or whatever it is that it...
| | |
by: Holger (David) Wagner |
last post by:
Hi all,
we're currently developing an application in the .NET environment that
needs to access a DLL implemented in Fortran. There is one procedure
with about 17 parameters, most of them arrays. After some trial and
error experiments, we've found out that
a) the parameters must be ordered by type, i.e. we cannot mix double,
integers and Strings (char-Arrays) - instead, we first need to put
all the float-Arrays and Int32-Arrays, and...
|
by: David Dvali |
last post by:
Hello.
I have one small program which I need to convert in C#.
The original source codes are written in Fortran 77.
Can anybody advice me what is the easy way to do this task?
Or may be there is some tools for it?
Thank you.
|
by: Nomad.C |
last post by:
Hi
I've been thinking of learning Fortran as number crunching kinda
language for my Physics degree......but then looking around the
internet, people are saying that the libraries/ Algorithms once used
for number crunching is now slowly converting into C, so do you think
I should stick with C, since I know C already, or should I proceed
learning fortran??
Any advice??
Thanks
|
by: luis |
last post by:
I'm using ctypes to call a fortran dll from python. I have no problems
passing integer and double arryas, but I have an error with str arrys.
For example:
.....
StringVector = c_char_p * len(id) # id is a list of strings
Id_dat=StringVector()
for i in range(len(Id)):
....Id_dat=id
|
by: marktang |
last post by:
ONU (Optical Network Unit) is one of the key components for providing high-speed Internet services. Its primary function is to act as an endpoint device located at the user's premises. However, people are often confused as to whether an ONU can Work As a Router. In this blog post, we’ll explore What is ONU, What Is Router, ONU & Router’s main usage, and What is the difference between ONU and Router. Let’s take a closer look !
Part I. Meaning of...
|
by: jinu1996 |
last post by:
In today's digital age, having a compelling online presence is paramount for businesses aiming to thrive in a competitive landscape. At the heart of this digital strategy lies an intricately woven tapestry of website design and digital marketing. It's not merely about having a website; it's about crafting an immersive digital experience that captivates audiences and drives business growth.
The Art of Business Website Design
Your website is...
| | |
by: Hystou |
last post by:
Overview:
Windows 11 and 10 have less user interface control over operating system update behaviour than previous versions of Windows. In Windows 11 and 10, there is no way to turn off the Windows Update option using the Control Panel or Settings app; it automatically checks for updates and installs any it finds, whether you like it or not. For most users, this new feature is actually very convenient. If you want to control the update process,...
|
by: agi2029 |
last post by:
Let's talk about the concept of autonomous AI software engineers and no-code agents. These AIs are designed to manage the entire lifecycle of a software development project—planning, coding, testing, and deployment—without human intervention. Imagine an AI that can take a project description, break it down, write the code, debug it, and then launch it, all on its own....
Now, this would greatly impact the work of software developers. The idea...
|
by: isladogs |
last post by:
The next Access Europe User Group meeting will be on Wednesday 1 May 2024 starting at 18:00 UK time (6PM UTC+1) and finishing by 19:30 (7.30PM).
In this session, we are pleased to welcome a new presenter, Adolph Dupré who will be discussing some powerful techniques for using class modules.
He will explain when you may want to use classes instead of User Defined Types (UDT). For example, to manage the data in unbound forms.
Adolph will...
|
by: adsilva |
last post by:
A Windows Forms form does not have the event Unload, like VB6. What one acts like?
|
by: 6302768590 |
last post by:
Hai team
i want code for transfer the data from one system to another through IP address by using C# our system has to for every 5mins then we have to update the data what the data is updated we have to send another system
|
by: muto222 |
last post by:
How can i add a mobile payment intergratation into php mysql website.
| | |
by: bsmnconsultancy |
last post by:
In today's digital era, a well-designed website is crucial for businesses looking to succeed. Whether you're a small business owner or a large corporation in Toronto, having a strong online presence can significantly impact your brand's success. BSMN Consultancy, a leader in Website Development in Toronto offers valuable insights into creating effective websites that not only look great but also perform exceptionally well. In this comprehensive...
| |
