From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Thread: 103376,47fc49812a5e8e38 X-Google-NewGroupId: yes X-Google-Thread: 1094ba,676bf5aacd30dd7b X-Google-NewGroupId: yes X-Google-Attributes: gida07f3367d7,gid8d3408f8c3,domainid0,public,usenet X-Google-Language: ENGLISH,ASCII Path: g2news2.google.com!news3.google.com!feeder.news-service.com!feeder3.cambriumusenet.nl!feed.tweaknews.nl!138.195.8.3.MISMATCH!news.ecp.fr!news.in2p3.fr!in2p3.fr!not-for-mail From: Vincent LAFAGE Newsgroups: comp.lang.ada,comp.lang.fortran Subject: Re: small example, using complex variables in Ada Date: Mon, 14 Jun 2010 15:00:40 +0200 Organization: In2p3 Message-ID: References: NNTP-Posting-Host: ipnnarval.in2p3.fr Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-Trace: ccpntc8.in2p3.fr 1276520437 18078 134.158.92.7 (14 Jun 2010 13:00:37 GMT) X-Complaints-To: newsmaster@cc.in2p3.fr NNTP-Posting-Date: Mon, 14 Jun 2010 13:00:37 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1.9) Gecko/20100515 Lightning/1.0b1 Icedove/3.0.4 In-Reply-To: Xref: g2news2.google.com comp.lang.ada:12678 comp.lang.fortran:26884 Date: 2010-06-14T15:00:40+02:00 List-Id: If we want not only compile-time warning but also run time check -fbounds-check like in gfortran -Wall -Wsurprising -Wconversion -fbounds-check dft.f90 -o dft It can be pretty useful, and close to some of the runtime checks of Ada. So, if we remember some larger scale results I provided in a former thread, with Ada and Fortran being equally good for coding numerical application, Fortran 90 is still twice as fast with complex... Vincent PS: on a completely different level, we may use less UPPERCASE, as most of us are more used to read lower-case or Capitalized. Particularly for reserved words. It's less work for our poor programmer's brain. The same goes for the languages' names as Fortran is no more in all-uppercase since Fortran 90, and ADA is the American Dental Association. ;) Le 14/06/2010 14:29, Nasser M. Abbasi a �crit : > On 6/14/2010 2:33 AM, Vincent LAFAGE wrote: > >> For instance, >> $ gfortran-4.3 -Wall -Wsurprising -Wconversion dft.f90 -o dft >> will reveal 11 surprising implicit conversion such as >> dft.f90:14.29: >> COMPLEX, parameter :: J =(0,1) >> 1 >> Warning: Conversion from INTEGER(4) to REAL(4) at (1) >> >> So "-Wall" is not the last word as far as warning are concerned. >> > > Thanks, I did not know about these flags. I am impressed now with FORTRAN. > > The f90 compiler, with those flags added, became as annoying, opps, I > mean as picky as the Ada compiler and complained about all the implicit > conversions. > > Also, with the use of lbound and ubound in FORTRAN helped make the logic > simpler by avoiding the 1-off problem. > > To update, below is the current version of the example in Ada and > FORTRAN. I also made a small page where I kept these for reference. > > http://12000.org/my_notes/mma_matlab_control/KERNEL/node94.htm > > I think now it seems to me, from this simple example, that Ada and > FORTRAN can be equally good languages for scientific applications. > > Thanks for everyone for the suggestions. > > ============= Ada ==================== > -- > -- dtf.adb, compiled with GNAT 4.3.4 20090804 (release) 1 > -- under CYGWIN 1.7.5 > -- $ gnatmake dft.adb > -- gcc -c dft.adb > -- gnatbind -x dft.ali > -- gnatlink dft.ali > -- $ ./dft.exe > -- > -- ( 6.00000E+00, 0.00000E+00) > -- (-1.50000E+00, 8.66026E-01) > -- (-1.50000E+00,-8.66025E-01) > > with Ada.Text_IO; use Ada.Text_IO; > with Ada.Numerics.Complex_Types; use Ada.Numerics.Complex_Types; > > with Ada.Numerics; use Ada.Numerics; > > with Ada.Numerics.Complex_Elementary_Functions; > use Ada.Numerics.Complex_Elementary_Functions; > > with Ada.Complex_Text_IO; use Ada.Complex_Text_IO; > > procedure dft is > N : constant := 3; -- named number, no conversion to Float needed > X : array(0 .. N-1) of Complex := (others=>(0.0,0.0)); > data : constant array(0 .. N-1) of float :=(1.0,2.0,3.0); > Two_Pi_Over_N : constant := 2 * Pi / N; > -- named number, outside the loop, like in ARM 3.3.2(9) > begin > FOR k in X'range LOOP > FOR m in data'range LOOP > X(k) := X(k) + data(m)*exp(-J*Two_Pi_Over_N * float(m*k)); > END LOOP; > put(X(k)); new_line; > END LOOP; > end dft; > > ====================== Fortran ====================== > ! dtf.f90, compiled with GCC 4.3.4 > ! under CYGWIN 1.7.5 > ! $ gfortran -Wall -Wsurprising -Wconversion dft.f90 > ! $ ./a.exe > ! ( 6.0000000 , 0.0000000 ) > ! ( -1.4999999 , 0.86602557 ) > ! ( -1.5000005 ,-0.86602497 ) > ! $ > > PROGRAM dft > > IMPLICIT NONE > > INTEGER, parameter :: N = 3 > COMPLEX, parameter :: J =(0.0,1.0) > REAL, parameter :: Pi = ACOS(-1.0) > INTEGER :: k,m > COMPLEX, dimension(0:N-1) :: X > REAL, dimension(0:N-1) :: data=(/1.0,2.0,3.0/) > REAL, parameter :: Two_Pi_Over_N = 2.0*Pi/real(N) > > DO k = lbound(X, 1), ubound(X, 1) > X(k)=(0.0,0.0) > DO m = lbound(data, 1), ubound(data, 1) > X(k) = X(k) + complex(data(m),0.0) & > * EXP(-J*complex(Two_Pi_Over_N*real(m*k),0.0)) > END DO > print *,X(k) > END DO > > END PROGRAM dft > > > --Nasser